Electrochemical detection in microcolumn separations.
AuthorsEwing AG, Mesaros JM, Gavin PF
JournalAnal Chem
PubMed ID8017638
Derivatization in capillary electrophoresis.
AuthorsBardelmeijer HA, Lingeman H, de Ruiter C, Underberg WJ
JournalJ Chromatogr A
PubMed ID9646486
'In recent years capillary electrophoresis (CE) has been developed into a versatile separation technique, next to gas and liquid chromatography (LC), well suited for the determination of a wide variety of e.g., pharmaceutical, biomedical and environmental samples. The main advantages of CE over chromatographic separation techniques are its simplicity and ... More
Focusing of nitric oxide mediated nitrosation and oxidative nitrosylation as a consequence of reaction with superoxide.
AuthorsEspey MG, Thomas DD, Miranda KM, Wink DA
JournalProc Natl Acad Sci U S A
PubMed ID12177414
'The impact of nitric oxide (NO) synthesis on different biological cascades can rapidly change dependent on the rate of NO formation and composition of the surrounding milieu. With this perspective, we used diaminonaphthalene (DAN) and diaminofluorescein (DAF) to examine the nitrosative chemistry derived from NO and superoxide (O2-) simultaneously generated ... More
Tumor cell-derived nitric oxide is involved in the immune-rejection of an immunogenic murine lymphoma.
AuthorsHu DE, Dyke SO, Moore AM, Thomsen LL, Brindle KM
JournalCancer Res
PubMed ID14729619
'The roles played by host-derived nitric oxide (NO) in the growth and subsequent immune rejection of a immunogenic murine lymphoma were investigated by growing the tumor in mice in which the gene for either inducible NO synthase (iNOS) or endothelial NOS (eNOS) had been ablated. This showed that NO from ... More
Biological activity of nitric oxide in the plasmatic compartment.
AuthorsWang X, Tanus-Santos JE, Reiter CD, Dejam A, Shiva S, Smith RD, Hogg N, Gladwin MT
JournalProc Natl Acad Sci U S A
PubMed ID15258287
'There exist reaction products of nitric oxide (NO) with blood that conserve its bioactivity and transduce an endocrine vasomotor function under certain conditions. Although S-nitrosated albumin has been considered the major species subserving this activity, recent data suggest that additional NO species, such as nitrite, nitrated lipids, N-nitrosamine, and iron-nitrosyl ... More
Violet light emitting diode-induced fluorescence detection combined with on-line sample concentration techniques for use in capillary electrophoresis.
AuthorsTsai CH, Huang HM, Lin CH
JournalElectrophoresis
PubMed ID12973813
'The first application of a violet light-emitting diode (LED) for fluorescence detection in capillary electrophoresis (CE) is described. The utility of violet LED (peak emission wavelength at 410 nm, approximately 2 mW) for fluorescence detection is demonstrated by examining reserpine and dopamine-labeled NDA (naphthalene-2,3-dicarboxaldehyde), respectively. The detection limit for reserpine ... More
Rho-kinase mediates hypoxia-induced downregulation of endothelial nitric oxide synthase.
AuthorsTakemoto M, Sun J, Hiroki J, Shimokawa H, Liao JK
JournalCirculation
PubMed ID12093770
'BACKGROUND: Hypoxia-induced pulmonary hypertension is a major cause of morbidity and mortality. Hypoxia induces pulmonary vasoconstriction, in part, by decreasing endothelial nitric oxide synthase (eNOS) expression. The mechanism by which hypoxia decreases eNOS expression is not known but may involve Rho-kinase-induced actin cytoskeletal changes in vascular endothelial cells. METHODS AND ... More
Laser ablation construction of on-column reagent addition devices for capillary electrophoresis.
'A simple and reproducible technique for constructing perfectly aligned gaps in fused-silica capillaries has been developed for postcolumn reagent addition with capillary electrophoresis. This technique uses laser ablation with the second harmonic of a Nd:YAG laser (532 nm) at 13.5 mJ/pulse and a repetition rate of 15 Hz to create ... More
Influence of kernel age on fumonisin B1 production in maize by Fusarium moniliforme.
AuthorsWarfield CY, Gilchrist DG
JournalAppl Environ Microbiol
PubMed ID10388675
'Production of fumonisins by Fusarium moniliforme on naturally infected maize ears is an important food safety concern due to the toxic nature of this class of mycotoxins. Assessing the potential risk of fumonisin production in developing maize ears prior to harvest requires an understanding of the regulation of toxin biosynthesis ... More
Reversed-phase liquid chromatography of the opioid peptides--2. Quantitative structure-retention relationships and isocratic retention prediction.
AuthorsDave K, Stobaugh JF, Riley CM
JournalJ Pharm Biomed Anal
PubMed ID1391083
'The ability of Snyder''s theory of linear gradient elution to predict the starting isocratic reversed-phase LC conditions (k'' = 4-10) for the opioid peptides was investigated. The errors in predicting the concentration of acetonitrile (phi) required to elute the peptides with a k'' value of 4 were high, ranging from ... More
Electrochemical characteristics of amino acids and peptides derivatized with naphthalene-2,3-dicarboxaldehyde: pH effects and differences in oxidation potentials.
AuthorsNussbaum MA, Przedwiecki JE, Staerk DU, Lunte SM, Riley CM
JournalAnal Chem
PubMed ID1621993
'The electrochemical oxidations of the cyanobenz[f]isoindole (CBI) derivatives of 18 amino acids and 15 peptides, including enkephalins and several enkephalin fragments, were studied. Cyclic voltammetry indicated that the oxidation potentials of derivatized amino acids were virtually independent of pH. The utility of this pH-independence was demonstrated by controlling, through varying ... More
Quantitation and stability of fumonisins B1 and B2 in milk.
AuthorsMaragos CM, Richard JL
JournalJ AOAC Int
PubMed ID7950418
'The well-documented presence of fumonisin mycotoxins B1 and B2 (FB1 and FB2) in corn raises the possibility that these toxins are carried over into the milk of animals fed with contaminated feed. The presence of FB1 and FB2 in milk has not been assessed because of the lack of sensitive ... More
Serotonin1B receptors in the ventral tegmental area modulate cocaine-induced increases in nucleus accumbens dopamine levels.
AuthorsO'Dell LE, Parsons LH
JournalJ Pharmacol Exp Ther
PubMed ID15226384
'Previous work has demonstrated that peripheral serotonin(1B) (5-HT(1B)) receptor agonist administration facilitates the behavioral and neurochemical effects of cocaine. This study used dual probe microdialysis to investigate whether activation of serotonin(1B) (5-HT(1B)) receptors in the ventral tegmental area (VTA) alters the ability of peripherally administered cocaine to elevate dopamine (DA) ... More
Dysregulation of IFN-gamma signaling pathways in the absence of TGF-beta 1.
AuthorsMcCartney-Francis NL, Wahl SM
JournalJ Immunol
PubMed ID12421979
'Deficiency of TGF-beta1 is associated with immune dysregulation and autoimmunity as exemplified by the multifocal inflammatory lesions and early demise of the TGF-beta1 null mice. Elevated NO metabolites (nitrite and nitrate) in the plasma of these mice suggest a participatory role of NO in the pathogenic inflammatory response. To determine ... More
Regulation of amiloride-sensitive Na(+) transport by basal nitric oxide.
AuthorsHardiman KM, McNicholas-Bevensee CM, Fortenberry J, Myles CT, Malik B, Eaton DC, Matalon S
JournalAm J Respir Cell Mol Biol
PubMed ID14607816
'We investigated the mechanisms of endogenous nitric oxide (NO) modulation of lung sodium (Na(+)) transport. C57BL/6 mice injected intraperitoneally with the specific inducible NO synthase (iNOS) inhibitor 1400W (10 mg/kg every 8 h for 72 h) exhibited decreased alveolar nitrite levels and Na(+)-dependent amiloride-sensitive alveolar fluid clearance as compared with ... More
Vapor and liquid phase detection of cyanide on a microchip.
AuthorsLu Q, Collins GE, Evans T, Hammond M, Wang J, Mulchandani A
JournalElectrophoresis
PubMed ID14730575
'A capillary electrophoresis microchip is used to selectively and sensitively monitor cyanide levels in both vapor (HCN((g))) and aqueous (NaCN in drinking water) phases. Laser-induced fluorescence detection is applied using a violet diode laser to monitor the fluorescent isoindole derivative formed by the reaction of cyanide with 2,3-naphthalenedicarboxaldehyde (NDA) and ... More
Analysis of the stability of amino acids derivatized with naphthalene-2,3-dicarboxaldehyde using high-performance liquid chromatography and mass spectrometry.
AuthorsManica DP, Lapos JA, Jones AD, Ewing AG
JournalAnal Biochem
PubMed ID14705782
'The stability of amino acids derivatized with naphthalene-2,3-dicarboxaldehyde (NDA) was investigated using a combination of high-performance liquid chromatography, solid-phase extraction, photodiode array spectrophotometric detection, and mass spectrometric (MS) characterization. The degradation of amino acid derivatives, generated using beta-mercaptoethanol as a nucleophile, was characterized under a variety of environmental influences, with ... More
Determination of fluorescent cyanobenz[f]isoindole derivatives of dopamine and norepinephrine using high performance liquid chromatography with chemiluminescence detection.
AuthorsKawasaki T, Imai K, Higuchi T, Wong OS
JournalBiomed Chromatogr
PubMed ID2383692
'Dopamine (DA), norepinephrine (NE) and 3,4-dihydroxybenzylamine (DHBA) are converted to highly fluorescent cyanobenz[f]isoindole (CBI) derivatives by reacting these amines with naphthalene-2,3-dicarboxaldehyde in the presence of cyanide ion. Femtomole amounts of these CBI derivatives separated by reverse-phase high performance liquid chromatography can be detected by a post-column chemiluminescence system utilizing bis(2,4-dinitrophenyl) ... More
High-performance liquid chromatographic assay of asymmetric dimethylarginine, symmetric dimethylarginine, and arginine in human plasma by derivatization with naphthalene-2,3-dicarboxaldehyde.
AuthorsMarra M, Bonfigli AR, Testa R, Testa I, Gambini A, Coppa G
JournalAnal Biochem
PubMed ID12782025
'Asymmetric dimethylarginine (ADMA) is an emerging cardiovascular risk factor. Its increased levels have been hypothesized to be a cause of endothelial dysfunction in pathological conditions such as hypertension, dyslipidemia, renal failure, hyperglycemia, and hyperhomocysteinemia. It acts as a potent competitive inhibitor of nitric oxide synthase. Methods using ortho-phthaldialdehyde (OPA) as ... More
Estrogen induces nitric oxide production via activation of constitutive nitric oxide synthases in human neuroblastoma cells.
AuthorsXia Y, Krukoff TL
JournalEndocrinology
PubMed ID15242984
'Although it is becoming increasingly evident that nitric oxide (NO) mediates some of estrogen''s actions in the brain, the effects of estrogen on NO production through NO synthases (NOS) in neuronal cells have not yet been identified. Here we assessed changes in NO production induced by 17beta-estradiol (E2) in cells ... More
Simultaneous determination of methamphetamine and its metabolites in the urine samples of abusers by high performance liquid chromatography with chemiluminescence detection.
AuthorsHayakawa K, Miyoshi Y, Kurimoto H, Matsushima Y, Takayama N, Tanaka S, Miyazaki M
JournalBiol Pharm Bull
PubMed ID7903574
'A HPLC determination method for methamphetamine (MA) and its metabolites in the urine samples of abusers has been developed. MA, amphetamine (AP), norephedrine (NE), p-hydroxymethamphetamine (pOHMA), p-hydroxyamphetamine (pOHAP) and an internal standard, namely beta-phenylethylamine (PEA) were derivatized with dansyl chloride. They were separated on a reversed phase column with gradient ... More
In vivo monitoring of glutathione and cysteine in rat caudate nucleus using microdialysis on-line with capillary zone electrophoresis-laser induced fluorescence detection.
AuthorsLada MW, Kennedy RT
JournalJ Neurosci Methods
PubMed ID9133579
'A fully-automated method for monitoring thiols in vivo using microdialysis coupled on-line with capillary zone electrophoresis with laser-induced fluorescence detection was developed. Dialysates were derivatized on-line with monobromobimane and automatically transferred to the separation capillary by a flow-gated interface. Analytes were detected on-column using the 2 mW, 354 nm line ... More
S-nitrosylation of matrix metalloproteinases: signaling pathway to neuronal cell death.
AuthorsGu Z, Kaul M, Yan B, Kridel SJ, Cui J, Strongin A, Smith JW, Liddington RC, Lipton SA
JournalScience
PubMed ID12183632
'Matrix metalloproteinases (MMPs) are implicated in the pathogenesis of neurodegenerative diseases and stroke. However, the mechanism of MMP activation remains unclear. We report that MMP activation involves S-nitrosylation. During cerebral ischemia in vivo, MMP-9 colocalized with neuronal nitric oxide synthase. S-Nitrosylation activated MMP-9 in vitro and induced neuronal apoptosis. Mass ... More
Naphthalene dicarboxaldehyde as an electrophilic fluorogenic moiety for affinity labeling: application to opioid receptor affinity labels with greatly improved fluorogenic properties.
AuthorsMcCurdy CR, Le Bourdonnec B, Metzger TG, El Kouhen R, Zhang Y, Law PY, Portoghese PS
JournalJ Med Chem
PubMed ID12086475
'To develop ligands with fluorogenic properties amenable for following the kinetics of cross-linking to receptors, a naphthalene dicarboxaldehyde moiety has been attached to an opiate pharmacophore 2 and evaluated in mu-opioid receptors. The fluorescence of the benzo[f]isoindole formed upon cross-linking of mu-opioid receptors by 2 permitted the time-course of covalent ... More
HPLC-fluorescence detection and MEKC-LIF detection for the study of amino acids and catecholamines labelled with naphthalene-2,3-dicarboxyaldehyde.
AuthorsSiri N, Lacroix M, Garrigues JC, Poinsot V, Couderc F,
JournalElectrophoresis
PubMed ID17058305
'Naphthalene-2,3-dicarboxyaldehyde (NDA) is commonly used for detection of primary amines in conjunction with their separation with HPLC and CE. The fluorescence of the derivatives can be measured by a conventional fluorometer or via LIF. NDA is a reactive dye, which can replace o-phthaldehyde (OPA) and provides for derivatives which are ... More
Recent advances in methods for the analysis of catecholamines and their metabolites.
AuthorsTsunoda M
JournalAnal Bioanal Chem
PubMed ID16924378
'Catecholamines, for example epinephrine, norepinephrine, and dopamine, are widely distributed and are important neurotransmitters and hormones in mammalian species. Several methods have been developed for analysis of catecholamines and related compounds. Determination of catecholamines in biological fluids has enabled us to clarify the physiological role played by these amines. Catecholamine ... More
Development of a protocol for the automated analysis of amino acids in brain tissue samples and microdialysates.
AuthorsShah AJ, de Biasi V, Taylor SG, Roberts C, Hemmati P, Munton R, West A, Routledge C, Camilleri P
JournalJ Chromatogr B Biomed Sci Appl
PubMed ID10670729
'An automated precolumn derivatisation method has been developed for the measurement of fourteen amino acids in brain tissue and microdialysate samples. The method involves labelling amino acids with naphthalene-2,3-dicarboxaldehyde (NDA) in the presence of cyanide (CN-). The resulting highly stable N-substituted 1-cyanobenz[f]isoindole (CBI) derivatives were separated using a binary gradient ... More
Two-way arginine transport in human endothelial cells: TNF-alpha stimulation is restricted to system y(+).
AuthorsSala R, Rotoli BM, Colla E, Visigalli R, Parolari A, Bussolati O, Gazzola GC, Dall'Asta V
JournalAm J Physiol Cell Physiol
PubMed ID11742806
'Human umbilical vein endothelial cells transport arginine through two Na(+)-independent systems. System y(+)L is insensitive to N-ethylmaleimide (NEM), inhibited by L-leucine in the presence of Na(+), and referable to the expression of SLC7A6/y(+)LAT2, SLC7A7/y(+)LAT1, and SLC3A2/4F2hc. System y(+) is referable to the expression of SLC7A1/CAT1 and SLC7A2/CAT2B. Tumor necrosis factor-alpha ... More
Determination of alpha-difluoromethylornithine in blood by microdialysis sampling and capillary electrophoresis with UV detection.
AuthorsHu T, Zuo H, Riley CM, Stobaugh JF, Lunte SM
JournalJ Chromatogr A
PubMed ID8574393
'A procedure is described for the analysis of alpha-difluoromethylornithine (DFMO), an anti-cancer agent, in plasma microdialysis (MD) samples. DFMO has been shown to be effective alone or in combination with other agents in the treatment of several cancers. Precolumn derivatization of DFMO with naphthalene-2,3-dicarboxaldehyde-cyanide (NDA-CN) in pH 10.0 borate buffer ... More
Analysis of baclofen by capillary electrophoresis with laser-induced fluorescence detection.
AuthorsChiang MT, Chang SY, Whang CW
JournalJ Chromatogr A
PubMed ID10845802
'A new analytical method for baclofen (4-amino-3-p-chlorophenylbutyric acid) based on capillary electrophoretic separation and laser-induced fluorescence detection has been developed. Naphthalene-2,3-dicarboxaldehyde was used for precolumn derivatization of the non-fluorescent drug. Optimal separation and detection were obtained with an electrophoretic buffer of 50 mM sodium borate (pH 9.5) and a He-Cd ... More
High-performance liquid chromatographic determination of GS4071, a potent inhibitor of influenza neuraminidase, in plasma by precolumn fluorescence derivatization with naphthalenedialdehyde.
AuthorsEisenberg EJ, Cundy KC
JournalJ Chromatogr B Biomed Sci Appl
PubMed ID9824240
'GS4071 is a potent inhibitor of influenza neuraminidase. A precolumn fluorescence derivatization HPLC method is described for the analysis of GS4071 in rat plasma. Plasma samples were subjected to solid-phase extraction on C18 extraction columns. After extraction, GS4071 was derivatized with naphthalenedialdehyde in the presence of potassium cyanide to produce ... More
In vivo monitoring of extracellular noradrenaline and glutamate from rat brain cortex with 2-min microdialysis sampling using capillary electrophoresis with laser-induced fluorescence detection.
AuthorsRobert F, Bert L, Lambás-Señas L, Denoroy L, Renaud B
JournalJ Neurosci Methods
PubMed ID9007754
'The measurement of neurotransmitters by capillary electrophoresis (CE) has emerged as a reliable and sensitive method for microdialysis sample analysis. This paper describes a method which employs laser-induced fluorescence detection (LIFD) of catecholamines and excitatory amino acid derivatives formed after reaction with naphthalene-2,3-dicarboxaldehyde. On-line derivatization of very small volumes of ... More
Determination of naphthalene-2,3-dicarboxaldehyde-labeled amino acids by open tubular liquid chromatography with electrochemical detection.
AuthorsOates MD, Jorgenson JW
JournalAnal Chem
PubMed ID2719257
'Naphthalene-2,3-dicarboxaldehyde (NDA) has been investigated as a new derivatizing reagent for the electrochemical detection of tagged amino acids. Gradient elution allowed for the separation of 18 NDA-derivatized amino acids on an open tubular liquid chromatography column in less than 50 min. Gradient elution and electrochemical detection were found to be ... More
Determination of a cyclic heptapeptide, a novel fibrinogen receptor antagonist, in human plasma by high-performance liquid chromatography with automated pre-column derivatization, column switching and fluorescence detection.
AuthorsKline WF, Matuszewski BK, Hsieh JY
JournalJ Chromatogr
PubMed ID1328269
'A sensitive high-performance liquid chromatographic (HPLC) assay for the determination of the cyclic heptapeptide Ac-Cs-Asn-Dtc-Amf-Gly-Asp-Cys-OH (Dtc = beta,beta-dimethylthioproline, Amf = p-aminomethylphenylalanine) in human plasma has been developed. The key steps in the assay include: solid-phase extraction of the drug from plasma, chemical derivatization of the primary amino group with naphthalene-2,3-dicarboxyaldehyde ... More
Investigation of the metabolism of substance P in rat striatum by microdialysis sampling and capillary electrophoresis with laser-induced fluorescence detection.
AuthorsFreed AL, Cooper JD, Davies MI, Lunte SM
JournalJ Neurosci Methods
PubMed ID11489296
'The metabolism of substance P (SP) was investigated in rat striatum using in vivo microdialysis. Substance P was perfused for 5 h at 0.2 microl/min, and its metabolism was followed for over 13 h. The resulting samples were derivatized precolumn with naphthalene-2,3-dicarboxaldehyde (NDA)/cyanide, separated and detected by cyclodextrin-modified electrokinetic chromatography ... More
Formation of a pterin radical in the reaction of the heme domain of inducible nitric oxide synthase with oxygen.
AuthorsHurshman AR, Krebs C, Edmondson DE, Huynh BH, Marletta MA
JournalBiochemistry
PubMed ID10625434
'The heme domain (iNOS(heme)) of inducible nitric oxide synthase (NOS) was expressed in Escherichia coli and purified to homogeneity. Rapid freeze-quench (RFQ) EPR was used to monitor the reaction of the reduced iNOS(heme) with oxygen in the presence and absence of substrate. In these reactions, heme oxidation occurs at a ... More
Photographic detection of fluorescent-labelled oligodeoxynucleotide in the blotting format by peroxyoxalate chemiluminescence.
AuthorsKuroda N, Hosoki S, Nakashima K, Akiyama S, Givens R
JournalJ Biolumin Chemilumin
PubMed ID9633013
'The preparation of a fluorescent labelled oligonucleotide and its photographic detection by peroxyoxalate chemiluminescence (PO-CL) are described. Fluorescent labelling of an oligonucleotide (15-mer) was performed with naphthalene-2,3-dicarboxaldehyde to give an N-substituted 1-cyanobenz[f]isoindole (CBI) derivative (CBI-15-mer). For the photographic detection of CBI-15-mer, the bis(2,6-difluorophenyl) oxalate (DFPO)-dimethyl phthalate (DMP) system was selected ... More
Enhanced temporal resolution for the microdialysis monitoring of catecholamines and excitatory amino acids using capillary electrophoresis with laser-induced fluorescence detection. Analytical developments and in vitro validations.
AuthorsBert L, Robert F, Denoroy L, Stoppini L, Renaud B
JournalJ Chromatogr A
PubMed ID8997746
'This paper reports the development of a method based on capillary electrophoresis with laser-induced fluorescence detection for the simultaneous determination of catecholamines and excitatory amino acids on submicroliter microdialysis samples, with short analysis times (3 min or less), high sensitivity (nanomolar range, i.e., attomoles detected) and high separation efficiency (up ... More
Improved clean-up method for the enkephalins in plasma using immunoaffinity chromatography.
AuthorsHendrickson TL, Wilson GS
JournalJ Chromatogr B Biomed Appl
PubMed ID8205242
'A rapid and selective method of sample clean-up using immunoaffinity chromatography (IAC) was developed to isolate enkephalins from plasma. The enkephalin antibodies were produced utilizing novel protein carriers. Two antibodies, LE4H8 and 33FC6, were selected because of their moderate binding affinity and different epitopes. Enkephalin-spiked plasma was loaded onto the ... More
Quantitative amino acid analysis of individual snail neurons by open tubular liquid chromatography.
AuthorsOates MD, Cooper BR, Jorgenson JW
JournalAnal Chem
PubMed ID2400102
'A method is described for the determination of amino acids in individual cells. The amino acids are derivatized with naphthalene-2,3-dicarboxaldehyde and then analyzed by open tubular liquid chromatography with amperometric detection. The total volume present after derivatization is approximately 25 nL. It was possible to quantitatively determine 17 amino acids ... More
Comparison of capillary liquid chromatography vs capillary electrophoresis, using the same detector.
AuthorsHelboe T, Hansen SH
JournalBiomed Chromatogr
PubMed ID9646920
Determination of amino acids at subfemtomole levels by high-performance liquid chromatography with laser-induced fluorescence detection.
AuthorsRoach MC, Harmony MD
JournalAnal Chem
PubMed ID3565761
N-substituted 1-cyanobenz[f]isoindole: evaluation of fluorescence efficiencies of a new fluorogenic label for primary amines and amino acids.
AuthorsMatuszewski BK, Givens RS, Srinivasachar K, Carlson RG, Higuchi T
JournalAnal Chem
PubMed ID3592222
Modification of lysine residues in proteins to improve their recovery when using derivatizing reagents.
AuthorsOates MD, Jorgenson JW
JournalAnal Chem
PubMed ID2122765
The determination of 4,5-dioxovaleric acid in plant preparations and a procedure for the assay of L-alanine:4,5-dioxovaleric acid aminotransferase (EC 2.6.1.43) activity.
AuthorsPorra RJ, Klein O
JournalAnal Biochem
PubMed ID6976135
Automated precolumn derivatization of amino acids, small peptides, brain amines and drugs with primary amino groups for reversed-phase high-performance liquid chromatography using naphthalenedialdehyde as the fluorogenic label.
AuthorsKoning H, Wolf H, Venema K, Korf J
JournalJ Chromatogr
PubMed ID2127935
Microcolumn separations and the analysis of single cells.
AuthorsKennedy RT, Oates MD, Cooper BR, Nickerson B, Jorgenson JW
JournalScience
PubMed ID2675314
Capillary zone electrophoresis and open tubular liquid chromatography are two examples of an emerging area of analytical instrumentation known as microcolumn separations. The high resolution and small sample requirements of these methods make them suitable for the quantitative, multicomponent chemical analysis of single cells. Appropriate instrumentation for the analysis of ... More
Determination of endogenous peptides with in vitro ACE inhibitory activity in normotensive human plasma by the fluorometric HPLC method.
AuthorsMatsui T, Matsufuji H, Kawasaki T, Osajima Y
JournalBiosci Biotechnol Biochem
PubMed ID9214772
An in vitro degradation test of angiotensin (ANG) II or III in normotensive supine human plasma from 9 healthy male subjects confirmed the production of smaller ANG metabolites with angiotensin I-converting enzyme inhibitory activity. These metabolites were identified as ANG (3-8), ANG (5-8), and ANG (3-4), whose respective peptide concentrations ... More
High-speed separation of subnanomolar concentrations of noradrenaline and dopamine using capillary zone electrophoresis with laser-induced fluorescence detection.
AuthorsBert L, Robert F, Denoroy L, Renaud B
JournalElectrophoresis
PubMed ID8740172
Capillary zone electrophoresis with laser-induced fluorescence detection has been shown to give rapid separations with high resolution and sensitivity. These advantages are documented for catecholamines analysis in the present work, which shows that separation of subnanomolar concentrations of dopamine and noradrenaline (detection limits of 8.6 x 10(-11) M, corresponding to ... More
Separation of naphthalene-2,3-dicarboxaldehyde-derivatized-substance P and its metabolites by micellar electrokinetic chromatography.
AuthorsFreed AL, Lunte SM
JournalElectrophoresis
PubMed ID10879958
This paper describes the development of analytical methodology for the separation of naphthalene-2,3-dicarboxaldehyde (NDA)-derivatized substance P (CBI-SP) and five lysine-containing metabolites by micellar electrokinetic chromatography (MEKC). The effect of surfactant composition and organic modifiers on the separation was investigated. The final separation buffer consisted of 80 mM sodium cholate in ... More
High-performance liquid chromatographic determination of cyanide in human red blood cells by pre-column fluorescence derivatization.
AuthorsSano A, Takimoto N, Takitani S
JournalJ Chromatogr
PubMed ID1491032
A method for the determination of cyanide in human red cells has been developed. Cyanide was extracted from red cells by adding water and methanol, and then derivatized with 2,3-naphthalene-dialdehyde and taurine to give a fluorescent product, which was determined by reversed-phase high-performance liquid chromatography with fluorescence detection. The recovery ... More
Methods for detection of reactive metabolites of oxygen and nitrogen: in vitro and in vivo considerations.
AuthorsTarpey MM, Wink DA, Grisham MB
JournalAm J Physiol Regul Integr Comp Physiol
PubMed ID14761864
Facile detection of reactive oxygen and nitrogen species in biologic systems is often problematic. This is a result of the numerous cellular mechanisms, both enzymatic and nonenzymatic involved in their catabolism/decomposition, the complex and overlapping nature of their reactivities, as well as the often limited intracellular access of detector systems. ... More
Multidimensional liquid chromatography of opioid peptides: fluorogenic labelling, retention prediction and separation optimization.
AuthorsNicholson LM, Patel HB, Kristjansson F, Crowley SC, Dave K, Stobaugh JF, Riley CM
JournalJ Pharm Biomed Anal
PubMed ID2100627
The ultra-trace analysis of opioid peptides in biological samples can be achieved by multidimensional liquid chromatography with pre-column fluorogenic derivatization with naphthalene-2,3-dicarboxaldehyde in the presence of cyanide ion. However, in order to take full advantage of the high sensitivity possible with detectors based on laser-induced fluorescence or chemiluminescence, each component ... More
Probing single secretory vesicles with capillary electrophoresis.
AuthorsChiu DT, Lillard SJ, Scheller RH, Zare RN, Rodriguez-Cruz SE, Williams ER, Orwar O, Sandberg M, Lundqvist JA
JournalScience
PubMed ID9469805
Secretory vesicles obtained from the atrial gland of the gastropod mollusk Aplysia californica were chemically analyzed individually with a combination of optical trapping, capillary electrophoresis separation, and a laser-induced fluorescence detection. With the use of optical trapping, a single vesicle that had attoliters (10(-18) liters) of volume was introduced into ... More
A fluorometric method for the specific determination of serum arginine with 2,3-naphthalenedicarbaldehyde.
AuthorsMiura T, Kashiwamura M, Kimura M
JournalAnal Biochem
PubMed ID6476380
A specific and simple fluorometric method for the determination of serum arginine was developed which consists of (1) deproteinization of serum sample with 10% perchloric acid, (2) blocking thiol compounds with N-ethylmaleimide, (3) fluorescence reaction with 2,3-naphthalenedicarbaldehyde in 0.2 M borate buffer, pH 9.3, in the presence of beta-cyclodextrin (25 ... More
Evaluation of capillary electrophoresis with post-column derivatization and laser-induced fluorescence detection for the determination of substance P and its metabolites.
AuthorsKostel KL, Lunte SM
JournalJ Chromatogr B Biomed Sci Appl
PubMed ID9271126
A method for the detection of substance P and its metabolites using capillary electrophoresis with post-capillary derivatization and laser-induced fluorescence detection is described. The post-capillary chemical derivatization system employs naphthalene-2,3-dicarboxaldehyde and beta-mercaptoethanol. Two reactor designs were evaluated for the determination of substance P and its metabolites. The fluorescent spectroscopic properties ... More
High performance liquid chromatography determination of cyanide in urine by pre-column fluorescence derivatization.
AuthorsSano A, Takezawa M, Takitani S
JournalBiomed Chromatogr
PubMed ID2804427
A method for the determination of cyanide in human urine has been developed. The method is based on the reaction of cyanide with 2,3-naphthalenedialdehyde and taurine to give a fluorescent product for reversed-phase HPLC separation and fluorometric detection. After centrifugation followed by dilution of urine samples, the specimens could be ... More
Simultaneous determination of cyanide and thiocyanate in blood by ion chromatography with fluorescence and ultraviolet detection.
AuthorsChinaka S, Takayama N, Michigami Y, Ueda K
JournalJ Chromatogr B Biomed Sci Appl
PubMed ID9746250
An ion chromatographic method for the simultaneous determination of cyanide and thiocyanate in blood has been developed. After extraction by adding water and methanol to blood, cyanide was derivatized with 2,3-naphthalenedialdehyde and taurine to give a fluorescent product of 1-cyanobenz[f]isoindole. This compound was detected with high sensitivity by fluorometry and ... More
Quantitative amino acid analysis of subnanogram levels of protein by open tubular liquid chromatography.
AuthorsOates MD, Jorgenson JW
JournalAnal Chem
PubMed ID2400103
A method is described for the hydrolysis and quantitative amino acid analysis of as little as 0.1 ng (4 fmol) of protein. Hydrolysis is performed by using a gas-phase method. The resulting amino acids are derivatized with naphthalene-2,3-dicarboxaldehyde and then analyzed by open tubular liquid chromatography with amperometric detection. The ... More
Derivatization reactions for neurotransmitters and their automation.
AuthorsBovingdon ME, Webster RA
JournalJ Chromatogr B Biomed Appl
PubMed ID7820275
Many reagents suitable for the derivatization of neurotransmitters are selective for the amino function. Others, however, are selective for the carboxyl-, thiol- and hydroxyl function, and recently, reagents selective for more than one function have been produced. Interest persists in the established reagents, with their well understood behaviour which assists ... More
An isocratic high performance liquid chromatography method for the determination of GABA and glutamate in discrete regions of the rodent brain.
AuthorsClarke G, O'Mahony S, Malone G, Dinan TG
JournalJ Neurosci Methods
PubMed ID17064781
The amino acid neurotransmitters gamma-aminobutyric acid (GABA) and glutamate have been implicated in mood disorders and high performance liquid chromatography (HPLC) is an important method in their quantitation. This paper describes a method which employs either electrochemical or fluorescent detection of the amino acid derivatives formed by a reaction with ... More
Determination of dopamine, norepinephrine, and related trace amines by prechromatographic derivatization with naphthalene-2,3-dicarboxaldehyde.
AuthorsKawasaki T, Higuchi T, Imai K, Wong OS
JournalAnal Biochem
PubMed ID2510545
Dopamine, norepinephrine, octopamine, tyramine, and 3,4-dihydroxybenzylamine react readily with naphthalene-2,3-dicarboxaldehyde in the presence of cyanide ion under mild conditions to give highly fluorescent cyanobenz[f]isoindole (CBI) products. The CBI products exhibit good solution chemical stability. The high-fluorescence quantum efficiency of the CBI fluorophore and the ability to excite these adducts in ... More
Chiral separation of naphthalene-2,3-dialdehyde labelled peptides by cyclodextrin-modified electrokinetic chromatography.
AuthorsDeSilva K, Jiang Q, Kuwana T
JournalBiomed Chromatogr
PubMed ID8580702
The chiral separation of several dipeptide enantiomers, derivatized by naphthalene-2,3-dialdehyde (NDA), was achieved by use of cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC). The dipeptides contained one or two chiral centers. In the case of several dipeptides containing two chiral centers, all four of the optical isomers could be separated and baseline ... More
Measurement of plasma S-adenosylmethionine and S-adenosylhomocysteine as their fluorescent isoindoles.
AuthorsCapdevila A, Wagner C
JournalAnal Biochem
PubMed ID9866680
The low levels of S-adenosylmethionine (AdoMet) and S-adenosylhomocysteine (AdoHcy) in plasma can be measured by formation of the fluorescent isoindole derivatives of these compounds. The procedure involves an initial separation of AdoMet and AdoHcy in deproteinized plasma by HPLC on a C-8 column followed by derivatization with naphthalenedialdehyde and cyanide ... More
Determination of 4-amino-1-hydroxybutane-1,1-bisphosphonic acid in urine by automated pre-column derivatization with 2,3-naphthalene dicarboxyaldehyde and high-performance liquid chromatography with fluorescence detection.
AuthorsKline WF, Matuszewski BK, Bayne WF
JournalJ Chromatogr
PubMed ID2094701
A sensitive (5 ng/ml) method for the determination of 4-amino-1-hydroxybutane-1,1-bisphosphonic acid in human urine is described. The procedure includes (1) the isolation of the drug from urine by co-precipitation of its calcium salt with endogenous phosphates in the presence of base, (2) a solid-phase anion-exchange sample clean-up and (3) automated ... More
Integrated microchip-device for the digestion, separation and postcolumn labeling of proteins and peptides.
AuthorsGottschlich N, Culbertson CT, McKnight TE, Jacobson SC, Ramsey JM
JournalJ Chromatogr B Biomed Sci Appl
PubMed ID10997719
A microchip device was demonstrated that integrated enzymatic reactions, electrophoretic separation of the reactants from the products and post-separation labeling of proteins and peptides prior to detection. A tryptic digestion of oxidized insulin B-chain was performed in 15 min under stopped flow conditions in a heated channel, and the separation ... More
Selective fluorogenic derivatization of a peptide nucleic acid trimer with naphthalene-2,3-dicarboxaldehyde.
AuthorsNerurkar MM, Rose MJ, Stobaugh JF, Borchardt RT
JournalJ Pharm Biomed Anal
PubMed ID9160260
The reversed-phase high-performance liquid chromatography of a Peptide Nucleic Acid (PNA) trimer has been studied after its preseparation fluorogenic derivatization with naphthalene-2,3-dicarboxaldehyde in the presence of cyanide (NDA/CN). Trace levels of the PNA trimer were determined in cell homogenate samples containing the PNA trimer at prederivatization concentrations as low as ... More
Chemiluminescence: a sensitive and versatile method for analyte detection.
AuthorsGivens RS, Jencen DA, Riley CM, Stobaugh JF, Chokshi H, Hanaoka N
JournalJ Pharm Biomed Anal
PubMed ID2093385
The generation of light from the oxidation of oxalic esters with hydrogen peroxide has been applied to the detection of luminescent materials. In order to improve the efficiency of this method, which is less than 0.1%, and to enhance the selectivity for target analytes, an in-depth investigation of the oxalate ... More
Analysis of single cells by capillary electrophoresis with on-column derivatization and laser-induced fluorescence detection.
AuthorsGilman SD, Ewing AG
JournalAnal Chem
PubMed ID7864392
On-column derivatization of single mammalian cells with capillary electrophoretic separation and laser-induced fluorescence detection is described. Individual cells are electrophorectically injected into the front end of the separation capillary, which is used as a chamber to lyse the cell and derivatize its contents for subsequent separation and detection. Reagents to ... More
Determination of free aspartic acid enantiomers in rat brain by capillary electrophoresis with laser-induced fluorescence detection.
AuthorsZhao S, Feng Y, LeBlanc MH, Liu YM
JournalJ Chromatogr B Biomed Sci Appl
PubMed ID11589464
Quantification of aspartic acid enantiomers in rat brain by using a chiral capillary electrophoresis procedure is described. Amino acids were pre-column derivatized with naphthalene-2,3-dialdehyde. Enantiomeric separation was achieved by micellar electrokinetic chromatography in the presence of methanol and beta-cyclodextrin as chiral selector. The chiral separation was coupled with laser-induced fluorescence ... More
Plasma analysis of alpha-difluoromethylornithine using pre-column derivatization with naphthalene-2,3-dicarboxaldehyde/CN and multidimensional chromatography.
AuthorsKilkenny ML, Slavik M, Riley CM, Stobaugh JF
JournalJ Pharm Biomed Anal
PubMed ID9884211
A procedure for the plasma analysis of alpha-difluoromethylornithine (DFMO) has been developed that utilizes pre-column derivatization with naphthalene-2,3-dicarboxaldehyde/cyanide (NDA/CN) in pH 9.2 borate buffer. Selective derivatization of delta-amine of DFMO followed by quenching of the reaction results in the formation of a cyanobenz [f] isoindole (CBI) derivative that is stable ... More
Fluorescence-based microtiter plate assay for glutamate-cysteine ligase activity.
AuthorsWhite CC, Viernes H, Krejsa CM, Botta D, Kavanagh TJ
JournalAnal Biochem
PubMed ID12814619
Glutamate-cysteine ligase (GCL; also known as gamma-glutamylcysteine synthetase) is the rate-limiting enzyme in glutathione (GSH) synthesis. Traditional assays for the activity of this enzyme are based either on coupled reactions with other enzymes or on high-performance liquid chromatography (HPLC) assessment of gamma-glutamylcysteine (gamma-GC) product formation. We took advantage of the ... More
Fluorogenic reactions for biomedical chromatography.
AuthorsOhkura Y, Kai M, Nohta H
JournalJ Chromatogr B Biomed Appl
PubMed ID7820282
A number of fluorogenic reactions, which have been used for HPLC detection systems by means of pre- and/or postcolumn derivatization, are surveyed with respect to both sensitivity and selectivity for the determination of biomedically important substances. For the derivatization of the substances, two types of fluorogenic reactions, fluorescence-generating and fluorescence-tagging, ... More
Naphthalene- and anthracene-2,3-dialdehyde as precolumn labelling reagents for primary amines using reversed- and normal-phase liquid chromatography with peroxyoxalate chemiluminescence detection.
AuthorsKwakman PJ, Koelewijn H, Kool I, Brinkman UA, De Jong GJ
JournalJ Chromatogr
PubMed ID2120277
Naphthalene-2,3-dialdehyde (NDA) and anthracene-2,3-dialdehyde (ADA) were applied as pre-column labelling reagents for the peroxyoxalate chemiluminescence detection of primary amines. The advantages of these labels are the selective derivatization reaction with primary amines and the good chemiluminescence properties. A serious disadvantage is the formation of cyanide-induced side-products which are major interferences ... More
Generation and detection of hydroxyl radical in vivo in rat spinal cord by microdialysis administration of Fenton's reagents and microdialysis sampling.
AuthorsLiu D
JournalJ Biochem Biophys Methods
PubMed ID8308193
We developed a double microdialysis fiber technique to generate hydroxyl radicals (OH.) in rat spinal cord. H2O2 and FeCl2/EDTA were pumped through two parallel microdialysis fibers inserted into the spinal cord such that the reactants mix in the tissue to generate OH. by the Fenton reaction. Generated OH. was detected ... More
Determination of enterostatin in human cerebrospinal fluid by capillary electrophoresis with laser induced fluorescence detection.
AuthorsZhao S, Prasad C, Robertson HJ, Liu YM
JournalFresenius J Anal Chem
PubMed ID11293697
A capillary electrophoresis (CE) method with laser induced fluorescence (LIF) detection is described for quantification of enterostatin (Val-Pro-Asp-Pro-Arg), a pentapeptide involved in appetite regulation and insulin secretion. Enterostatin and two other pentapeptides belonging to the enterostatin family (i.e. Ala-Pro-Gly-Pro-Arg and Val-Pro-Gly-Pro-Arg) were well separated from each other. The peptides were ... More
Electrogenerated chemiluminescence detection in reversed-phase liquid chromatography.
AuthorsFowry SP, Wightman RM
JournalAnal Chem
PubMed ID11838670
Electrogenerated chemiluminescence (ECL) has been developed as a detection method for liquid chromatography. The radical cation of tri-p-tolylamine (TPTA) is used as a common electron acceptor for the electrogenerated radical anions of a variety of organic analytes. ECL is accomplished with a high-frequency potential pulse program applied to a microelectrode ... More
Liquid chromatographic determination of fumonisins B1, B2, and B3 in corn silage.
AuthorsKim EK, Maragos CM, Kendra DF
JournalJ Agric Food Chem
PubMed ID14733494
Corn silage was dried, ground, and then extracted with 0.1 M ethylenediaminetetraacetic acid. The filtrate was applied to a FumoniTest immunoaffinity column. Fumonisins were derivatized with naphthalene-2,3-dicarboxaldehyde, separated on a C(18) liquid chromatographic column, and detected by fluorescence. The detection limits for fumonisin B(1), fumonisin B(2), and fumonisin B(3) were ... More
Measurement of 4,5-dioxovaleric acid by high-performance liquid chromatography and fluorescence detection.
AuthorsUmmus RE, Onuki J, Dörnemann D, Medeiros MH, Di Mascio P
JournalJ Chromatogr B Biomed Sci Appl
PubMed ID10410948
In this work we describe a sensitive method for the detection of 4,5-dioxovaleric acid (DOVA). 4,5-Dioxovaleric acid is derivatized with 2,3-diaminonaphthalene to form 3-(benzoquinoxalinyl-2)propionic acid (BZQ), a product with favorable UV absorbance and fluorescence properties. The high-performance liquid chromatographic method with UV absorbance and fluorescence detection is simple and its ... More
Reversed-phase ion-pair liquid chromatography of the angiotensins.
AuthorsPatel HB, Stobaugh JF, Riley CM
JournalJ Chromatogr
PubMed ID2050775
The isocratic reversed-phase liquid chromatography of the angiotensins and a number of their synthetic analogues is described. Complete separation of 10 out of 12 peptides was achieved through a solvent optimization strategy with a total analysis time of about 20 min. The retention behavior of the angiotensins studied was described ... More
Agmatine reverses pain induced by inflammation, neuropathy, and spinal cord injury.
AuthorsFairbanks CA, Schreiber KL, Brewer KL, Yu CG, Stone LS, Kitto KF, Nguyen HO, Grocholski BM, Shoeman DW, Kehl LJ, Regunathan S, Reis DJ, Yezierski RP, Wilcox GL
JournalProc Natl Acad Sci U S A
PubMed ID10984543
Antagonists of glutamate receptors of the N-methyl-d-aspartate subclass (NMDAR) or inhibitors of nitric oxide synthase (NOS) prevent nervous system plasticity. Inflammatory and neuropathic pain rely on plasticity, presenting a clinical opportunity for the use of NMDAR antagonists and NOS inhibitors in chronic pain. Agmatine (AG), an endogenous neuromodulator present in ... More
Analysis of fumonisin B1 in corn by capillary electrophoresis.
AuthorsMaragos CM, Bennett GA, Richard JL
JournalAdv Exp Med Biol
PubMed ID8850609
Intact fumonisins contain two tricarballylic acid groups and can therefore acquire a net negative charge. The anionic nature of the fumonisins is the basis behind the widely used method for cleanup of corn with strong anion exchange (SAX) columns. This property also enables the fumonisins to be separated by electrophoretic ... More
Determination of the anticancer drug, 15-deoxyspergualin, in plasma ultrafiltrate by liquid chromatography and precolumn derivatization with naphthalene-2,3-dicarboxaldehyde/cyanide.
AuthorsSprancmanis LA, Riley CM, Stobaugh JF
JournalJ Pharm Biomed Anal
PubMed ID2094416
An alternative analytical method for the determination of 15-deoxyspergualin in plasma is described. The drug was initially separated from the plasma matrix by ultrafiltration and a precolumn derivatization step was performed with naphthalene-2,3-dicarboxaldehyde in the presence of sodium cyanide to yield the fluorescent N-substituted 1-cyanobenz[f]isoindole (CBI) derivative. The CBI derivative ... More
Reversed-phase liquid chromatography of the opioid peptides. 3. Development of a microanalytical system for opioid peptides involving microbore liquid chromatography, post-column derivatization and laser-induced fluorescence detection.
AuthorsDave KJ, Stobaugh JF, Rossi TM, Riley CM
JournalJ Pharm Biomed Anal
PubMed ID1298404
A microanalytical system has been developed for the determination of peptides in small samples. Naphthalene-2,3-dicarboxaldehyde-beta-mercaptoethanol (NDA-BME) was used as the labelling reagent system as an alternative to NDA-cyanide (NDA-CN) because of the faster labelling when CN was replaced by a thiol. The fluorescence characteristics of the NDA-thiol adducts, N-substituted 1-alkylthiobenz[f]isoindoles ... More
Post-column fluorescence derivatization of proteins and peptides in capillary electrophoresis with a sheath flow reactor and 488 nm argon ion laser excitation.
AuthorsYe M, Hu S, Quigley WW, Dovichi NJ
JournalJ Chromatogr A
PubMed ID14753787
We report the use of a sheath flow reactor for post-column fluorescence derivatization of proteins. The derivatization reaction employed naphthalene-2,3-dicarboxaldehyde (NDA) and beta-mercaptoethanol, which were added in the sheath buffer. The labeled proteins were detected by laser-induced fluorescence with an argon-ion laser beam at 488 nm. The performance of this ... More
Separation and characterization of amines from individual atrial gland vesicles of Aplysia californica.
AuthorsLillard SJ, Chiu DT, Scheller RH, Zare RN, Rodríguez-Cruz SE, Williams ER, Orwar O, Sandberg M, Lundqvist JA
JournalAnal Chem
PubMed ID9737203
Several amine-containing components of individual vesicles from the atrial gland of Aplysia californica were identified with capillary electrophoresis (CE). On-line derivatization with naphthalene-2,3-dicarboxaldehyde was performed, and the derivatized amine-containing components were detected with laser-induced fluorescence (LIF). Amino acids, including taurine, that had not been determined previously in atrial gland vesicles ... More
Capillary electrophoretic separation of glutamate enantiomers in neural samples.
AuthorsQuan Z, Liu YM
JournalElectrophoresis
PubMed ID12658700
A micellar electrokinetic chromatographic (MEKC) separation of glutamate (Glu) enantiomers fluorescently tagged with naphthalene-2,3-dicarboxaldehyde (NDA) is described. Chiral selectors tested included alpha-, beta-, and gamma-cyclodextrins, modified cyclodextrins, D-glucosamine, sucrose, taurocholate, and their binary mixtures. NDA-labeled Glu enantiomers were best resolved with beta-cyclodextrin in the presence of methanol as an organic ... More
Tissue plasminogen activator mediates microglial activation via its finger domain through annexin II.
AuthorsSiao CJ, Tsirka SE
JournalJ Neurosci
PubMed ID11978811
Microglia are the immunocompetent cells of the CNS, and their activation is thought to play an important neurotoxic role in many diseases modeled by glutamate-induced excitotoxicity. One molecule whose expression is upregulated after excitotoxic injury is tissue plasminogen activator (tPA), a serine protease with dual roles in the CNS. The ... More
Chiral analysis of baclofen by alpha-cyclodextrin-modified capillary electrophoresis and laser-induced fluorescence detection.
AuthorsChiang MT, Chang SY, Whang CW
JournalElectrophoresis
PubMed ID11197160
An enantioselective method for baclofen (4-amino-3-p-chlorophenylbutyric acid) based on capillary electrophoresis (CE) separation and laser-induced fluorescence (LIF) detection has been developed. Naphthalene-2,3-dicarboxaldehyde (NDA) was used for precolumn derivatization of the nonfluorescent drug. alpha-Cyclodextrin (alpha-CD) was included in the buffer as a chiral selector for the separation of NDA-labeled S-(+)- and ... More
Role of surfactant protein-A in nitric oxide production and mycoplasma killing in congenic C57BL/6 mice.
AuthorsHickman-Davis JM, Gibbs-Erwin J, Lindsey JR, Matalon S
JournalAm J Respir Cell Mol Biol
PubMed ID12959946
We generated congenic surfactant protein A (SP-A)-deficient (SP-A[-/-]) mice on the mycoplasma resistant C57BL/6 background (B6.SP-A[-/-]) and characterized their response to mycoplasma infection in comparison to C57BL/6 (B6) mice. B6.SP-A(-/-) mice infected with 10(6) colony-forming units (cfu) of Mycoplasma pulmonis had significantly higher bacterial lung loads than B6 mice at ... More
Matrix-assisted laser desorption/ionization time-of-flight and nano-electrospray ionization ion trap mass spectrometric characterization of 1-cyano-2-substituted-benz[f]isoindole derivatives of peptides for fluorescence detection.
AuthorsLinnemayr K, Brückner A, Körner R, Hahn R, Jungbauer A, Josic D, Roepstorff P, Rizzi A, Allmaier G
JournalJ Mass Spectrom
PubMed ID10226367
A series of hexa- to decapeptides (molecular mass range 800-1200) were labeled with naphthalene-2,3-dicarboxaldehyde, which preferentially reacts with the primary amino groups of a peptide. A highly stable peptide conjugate is formed, which allows selective analysis by fluorescence at excitation and emission wavelengths of 420 and 490 nm, respectively. After ... More
Expression and regulation of inducible nitric oxide synthase from human primary airway epithelial cells.
AuthorsDonnelly LE, Barnes PJ
JournalAm J Respir Cell Mol Biol
PubMed ID11751214
Elevated levels of exhaled nitric oxide are seen in inflammatory airway diseases such as asthma, but the cellular source remains unknown. This study investigated whether human airway epithelial cells express inducible nitric oxide synthase (iNOS). Human bronchial epithelial cells stimulated with 50 ng/ml interleukin-1beta, tumor necrosis factor-alpha, and interferon-gamma express ... More
A comparison of fluorescamine and naphthalene-2,3-dicarboxaldehyde fluorogenic reagents for microplate-based detection of amino acids.
AuthorsBantan-Polak T, Kassai M, Grant KB
JournalAnal Biochem
PubMed ID11673879
The use of appropriate fluorometric derivatization procedures is of considerable importance for accurate determination of amino acids in biological samples and in metal-assisted peptide hydrolysis reactions. It is especially critical for the relative fluorescence intensities (RFI) of equal amounts of amino acids to be as similar as possible. While fluorescamine ... More
Capillary zone electrophoresis with laser-induced fluorescence detection for the determination of nanomolar concentrations of noradrenaline and dopamine: application to brain microdialysate analysis.
AuthorsRobert F, Bert L, Denoroy L, Renaud B
JournalAnal Chem
PubMed ID9306734
Determination of catecholamines by capillary zone electrophoresis with laser-induced fluorescence detection was performed on low-concentration samples, which were derivatized with naphthalene-2,3-dicarboxaldehyde to give highly fluorescent compounds. When the borate concentration in the derivatization medium was decreased from 130 to 13 mM, sensitivity for noradrenaline (NA) and dopamine (DA) was greatly ... More
Monitoring cellular release with dynamic channel electrophoresis.
AuthorsLiu YM, Moroz T, Sweedler JV
JournalAnal Chem
PubMed ID9921124
A channel electrophoresis system consisting of a 50 microns by 75 mm by 25 mm separation channel has been adapted to follow stimulated release from individual and small groups of isolated neurons. The cells of interest are placed in a nanoperfusion chamber located near the exit of a sampling capillary. ... More
High-performance liquid chromatographic assay for the quantitation of L-arginine in human plasma.
AuthorsGopalakrishnan V, Burton PJ, Blaschke TF
JournalAnal Chem
PubMed ID8843144
L-Arginine is metabolized to nitric oxide by nitric oxide synthase, and abnormalities in nitric oxide production have been implicated in the pathogenesis of some diseases involving the vasculature. Thus, there has been interest in the effects of pharmacologic doses of L-arginine in patients with cardiovascular and renal diseases. To study ... More
Use of 2,3-naphthalenedicarboxaldehyde derivatization for single-cell analysis of glutathione by capillary electrophoresis and histochemical localization by fluorescence microscopy.
AuthorsOrwar O, Fishman HA, Ziv NE, Scheller RH, Zare RN
JournalAnal Chem
PubMed ID8633771
We report that 2,3-naphthalenedicarboxaldehyde reacts rapidly with glutathione and its precursor, gamma-glutamylcysteine, to form highly fluorescent derivatives under physiological conditions. In contrast to previous accounts of 2,3-naphthalenedicarboxaldehyde labeling of primary amines, no additional CN- ion or any other additional nucleophile is required. The fluorescence spectral properties of the chromophores (lambda ... More
Multiphoton-excited fluorescence of fluorogen-labeled neurotransmitters.
AuthorsShear JB, Brown EB, Webb WW
JournalAnal Chem
PubMed ID8651483
Fluorescence detection of fluorogen-labeled neurotransmitters is demonstrated using 100 fs pulses from a titanium-sapphire mode-locked laser to achieve molecular excitation by simultaneous absorption of two and three photons of near-IR radiation. Two-photon excitation spectra are determined for the naphthalene-2,3 dicarboxaldehyde derivative of glycine and the fluorescamine derivative of leucine enkephalin, ... More
In vivo simultaneous monitoring of gamma-aminobutyric acid, glutamate, and L-aspartate using brain microdialysis and capillary electrophoresis with laser-induced fluorescence detection: Analytical developments and in vitro/in vivo validations.
AuthorsSauvinet V, Parrot S, Benturquia N, Bravo-Moratón E, Renaud B, Denoroy L
JournalElectrophoresis
PubMed ID14518043
gamma-Aminobutyric acid (GABA), glutamate (Glu), and L-aspartate (L-Asp) are three major amino acid neurotransmitters in the central nervous system. In this work, a method for the separation of these three neurotransmitters in brain microdialysis samples using a commercially available capillary electrophoresis (CE) system has been developed. Molecules were tagged on ... More
Improved determination of the bisphosphonate alendronate in human plasma and urine by automated precolumn derivatization and high-performance liquid chromatography with fluorescence and electrochemical detection.
AuthorsKline WF, Matuszewski BK
JournalJ Chromatogr
PubMed ID1478982
An improved method for the determination of 4-amino-1-hydroxybutane-1,1-bisphosphonic acid (alendronate) in human urine and an assay in human plasma are described. The methods are based on co-precipitation of the bisphosphonate with calcium phosphates, automated pre-column derivatization of the primary amino group of the bisphosphonic acid with 2,3-naphthalene dicarboxyaldehyde (NDA)-N-acetyl-D-penicillamine (NAP) ... More