Tracking of quantum dot-labeled CFTR shows near immobilization by C-terminal PDZ interactions.
AuthorsHaggie PM, Kim JK, Lukacs GL, Verkman AS
JournalMol Biol Cell
PubMed ID16987954
'Mutations in cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-regulated chloride channel, cause cystic fibrosis. To investigate interactions of CFTR in living cells, we measured the diffusion of quantum dot-labeled CFTR molecules by single particle tracking. In multiple cell lines, including airway epithelia, CFTR diffused little in the plasma membrane, ... More
Tracking individual kinesin motors in living cells using single quantum-dot imaging.
AuthorsCourty S, Luccardini C, Bellaiche Y, Cappello G, Dahan M
JournalNano Lett
PubMed ID16834436
'We report a simple method using semiconductor quantum dots (QDs) to track the motion of intracellular proteins with a high sensitivity. We characterized the in vivo motion of individual QD-tagged kinesin motors in living HeLa cells. Single-molecule measurements provided important parameters of the motor, such as its velocity and processivity, ... More
Elucidation of intracellular recycling pathways leading to exocytosis of the Fc receptor, FcRn, by using multifocal plane microscopy.
AuthorsPrabhat P, Gan Z, Chao J, Ram S, Vaccaro C, Gibbons S, Ober RJ, Ward ES
JournalProc Natl Acad Sci U S A
PubMed ID17384151
'The intracellular events on the recycling pathway that lead from sorting endosomes to exocytosis at the plasma membrane are central to cellular function. However, despite intensive study, these processes are poorly characterized in spatial and dynamic terms. The primary reason for this is that, to date, it has not been ... More
Random walk of processive, quantum dot-labeled myosin Va molecules within the actin cortex of COS-7 cells.
AuthorsNelson SR, Ali MY, Trybus KM, Warshaw DM,
JournalBiophys J
PubMed ID19619465
'Myosin Va (myoVa) is an actin-based intracellular cargo transporter. In vitro experiments have established that a single myoVa moves processively along actin tracks, but less is known about how this motor operates within cells. Here we track the movement of a quantum dot (Qdot)-labeled myoVa HMM in COS-7 cells using ... More
Pegylated, steptavidin-conjugated quantum dots are effective detection elements for reverse-phase protein microarrays.
AuthorsGeho D, Lahar N, Gurnani P, Huebschman M, Herrmann P, Espina V, Shi A, Wulfkuhle J, Garner H, Petricoin E, Liotta LA, Rosenblatt KP
JournalBioconjug Chem
PubMed ID15898722
'Protein microarray technologies provide a means of investigating the proteomic content of clinical biopsy specimens in order to determine the relative activity of key nodes within cellular signaling pathways. A particular kind of protein microarray, the reverse-phase microarray, is being evaluated in clinical trials because of its potential to utilize ... More
Parallel detection of antigen-specific T-cell responses by multidimensional encoding of MHC multimers.
AuthorsHadrup SR, Bakker AH, Shu CJ, Andersen RS, van Veluw J, Hombrink P, Castermans E, Thor Straten P, Blank C, Haanen JB, Heemskerk MH, Schumacher TN,
JournalNat Methods
PubMed ID19543285
'The use of fluorescently labeled major histocompatibility complex multimers has become an essential technique for analyzing disease- and therapy-induced T-cell immunity. Whereas classical major histocompatibility complex multimer analyses are well-suited for the detection of immune responses to a few epitopes, limitations on human-subject sample size preclude a comprehensive analysis of ... More
Fluorescent nanocrystals for use in early cervical cancer detection.
AuthorsNida DL, Rahman MS, Carlson KD, Richards-Kortum R, Follen M
JournalGynecol Oncol
PubMed ID16139342
'BACKGROUND: Quantum dots (qdots) are a promising alternative to organic fluorophores for biological imaging. Advantages of quantum dots over organic fluorophores include broad excitation coupled with narrow, tunable emission, high resistance to chemical and metabolic degradation, a higher photobleaching threshold and finally the ability to be modified with a targeting ... More
Quantum dots for tracking dendritic cells and priming an immune response in vitro and in vivo.
AuthorsSen D, Deerinck TJ, Ellisman MH, Parker I, Cahalan MD,
JournalPLoS ONE
PubMed ID18820727
'Dendritic cells (DCs) play a key role in initiating adaptive immune response by presenting antigen to T cells in lymphoid organs. Here, we investigate the potential of quantum dots (QDs) as fluorescent nanoparticles for in vitro and in vivo imaging of DCs, and as a particle-based antigen-delivery system to enhance ... More
Prognostic value of Akt-1 in human prostate cancer: a computerized quantitative assessment with quantum dot technology.
AuthorsLi R, Dai H, Wheeler TM, Sayeeduddin M, Scardino PT, Frolov A, Ayala GE,
JournalClin Cancer Res
PubMed ID19417030
'BACKGROUND: Akt/protein kinase B signaling pathway has been implicated in tumorigenesis and progression. Previous studies showed the predictive potential of p-Akt-1, but total Akt-1 could provide more reliable information. We used image deconvolution, nanotechnology (quantum dots), and image analysis to improve Akt-1 quantification. DESIGN: This tissue microarray study included 840 ... More
Myosin Va maneuvers through actin intersections and diffuses along microtubules.
'Certain types of intracellular organelle transport to the cell periphery are thought to involve long-range movement on microtubules by kinesin with subsequent handoff to vertebrate myosin Va (myoVa) for local delivery on actin tracks. This process may involve direct interactions between these two processive motors. Here we demonstrate using single ... More
Separation of bioconjugated quantum dots using capillary electrophoresis.
AuthorsVicente G, Colón LA,
JournalAnal Chem
PubMed ID18278946
'Capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection was used to separate different bioconjugated CdSe/ZnS quantum dots (QDs). The QD nanocrystals studied were conjugated to the biomolecules streptavidin, biotin, and immunoglobulin G. The bioconjugated QDs showed different electrophoretic mobilities, which appear to depend upon the biomolecule that is attached to ... More
An oligonucleotide microarray for microRNA expression analysis based on labeling RNA with quantum dot and nanogold probe.
AuthorsLiang RQ, Li W, Li Y, Tan CY, Li JX, Jin YX, Ruan KC
JournalNucleic Acids Res
PubMed ID15684409
'MicroRNAs (miRNAs) play important regulatory roles in animals and plants by targeting mRNAs for cleavage or translational repression. They have diverse expression patterns and might regulate various developmental and physiological processes. Profiling miRNA expression is very helpful for studying biological functions of miRNAs. We report a novel miRNA profiling microarray, ... More
High accuracy 3D quantum dot tracking with multifocal plane microscopy for the study of fast intracellular dynamics in live cells.
AuthorsRam S, Prabhat P, Chao J, Ward ES, Ober RJ,
JournalBiophys J
PubMed ID18835896
'Single particle tracking in three dimensions in a live cell environment holds the promise of revealing important new biological insights. However, conventional microscopy-based imaging techniques are not well suited for fast three-dimensional (3D) tracking of single particles in cells. Previously we developed an imaging modality multifocal plane microscopy (MUM) to ... More
Automated four-color analysis of leukocytes by scanning fluorescence microscopy using quantum dots.
AuthorsBocsi J, Lenz D, Mittag A, Varga VS, Molnar B, Tulassay Z, Sack U, Tárnok A
JournalCytometry A
PubMed ID16479596
'BACKGROUND: Scanning fluorescence microscope (SFM) is a new technique for automated motorized microscopes to measure multiple fluorochrome labeled cells (Bocsi et al., Cytometry A 2004, 61:1-8). AIMS: We developed a four-color staining protocol (DNA, CD3, CD4, and CD8) for the lymphocyte phenotyping by SFM. METHODS: Organic (Alexa488, FITC, PE-Alexa610, CyChrom, ... More
Tracking individual proteins in living cells using single quantum dot imaging.
'Single quantum dot imaging is a powerful approach to probe the complex dynamics of individual biomolecules in living systems. Due to their remarkable photophysical properties and relatively small size, quantum dots can be used as ultrasensitive detection probes. They make possible the study of biological processes, both in the membrane ... More
Quantitative in situ detection of phosphoproteins in fixed tissues using quantum dot technology.
AuthorsBodo J, Durkin L, Hsi ED,
JournalJ Histochem Cytochem
PubMed ID19332430
'Detection and quantitation of phosphoproteins (PPs) in fixed tissues will become increasingly important as additional inhibitors of protein kinases enter clinical use and new disease entities are defined by molecular changes affecting PP levels. We characterize fixation conditions suitable for accurate PP quantitation that are achievable in a clinical laboratory ... More
Nanometer distance measurements between multicolor quantum dots.
'Quantum dot dimers made of short double-stranded DNA molecules labeled with different color quantum dots at each end were imaged using multicolor stage-scanning confocal microscopy. This approach eliminates chromatic aberration and color registration issues usually encountered in other multicolor imaging techniques. We demonstrate nanometer accuracy in individual distance measurement by ... More
Quantum dot mediated imaging of atherosclerosis.
AuthorsJayagopal A, Su YR, Blakemore JL, Linton MF, Fazio S, Haselton FR,
JournalNanotechnology
PubMed ID19420562
'The progression of atherosclerosis is associated with leukocyte infiltration within lesions. We describe a technique for the ex vivo imaging of cellular recruitment in atherogenesis which utilizes quantum dots (QD) to color-code different cell types within lesion areas. Spectrally distinct QD were coated with the cell-penetrating peptide maurocalcine to fluorescently-label ... More
The formation of acetylcholine receptor clusters visualized with quantum dots.
AuthorsGeng L, Zhang HL, Peng HB,
JournalBMC Neurosci
PubMed ID19604411
BACKGROUND: Motor innervation of skeletal muscle leads to the assembly of acetylcholine receptor (AChR) clusters in the postsynaptic membrane at the vertebrate neuromuscular junction (NMJ). Synaptic AChR aggregation, according to the diffusion-mediated trapping hypothesis, involves the establishment of a postsynaptic scaffold that ... More
A cell nanoinjector based on carbon nanotubes.
AuthorsChen X, Kis A, Zettl A, Bertozzi CR,
JournalProc Natl Acad Sci U S A
PubMed ID17485677
Technologies for introducing molecules into living cells are vital for probing the physical properties and biochemical interactions that govern the cell's behavior. Here, we report the development of a nanoscale cell injection system (termed the nanoinjector) that uses carbon nanotubes to deliver cargo into cells. A single multiwalled carbon nanotube ... More
Ligand-conjugated quantum dots monitor antigen uptake and processing by dendritic cells.
AuthorsCambi A, Lidke DS, Arndt-Jovin DJ, Figdor CG, Jovin TM
JournalNano Lett
PubMed ID17388641
The dendritic cell (DC) specific pathogen-uptake receptor (DC-SIGN) internalizes antigens for degradation and presentation onto MHC molecules. At the cell membrane, DC-SIGN forms nanoclusters that facilitate virus capture. However, internalized viruses, such as HIV-1, escape degradation. Here, we exploit ligand-conjugated, virus-sized, highly photostable quantum dots (QDs) to monitor in living ... More
Peptide-conjugated quantum dots activate neuronal receptors and initiate downstream signaling of neurite growth.
AuthorsVu TQ, Maddipati R, Blute TA, Nehilla BJ, Nusblat L, Desai TA
JournalNano Lett
PubMed ID15826094
Quantum dots (QDs) could serve as fluorescent scaffolds for effecting specific physiological and pharmacological responses in cells. Here, we conjugate the peptide ligand betaNGF to QD surfaces, and confirm surface modification and single QD nanostructure using AFM. We show that betaNGF-QDs retain bioactivity, activate TrkA receptors, and initiate neuronal differentiation ... More
Quantum dot ex vivo labeling of neuromuscular synapses.
Nicotinic receptors (nAchRs) are responsible for fast excitatory signaling by the neurotransmitter acetylcholine (Ach). They are present on the postsynaptic membrane at neuromuscular junctions (NMJs) and also at brain synapses. Alpha-bungarotoxin (alpha-BTX), a high-affinity nAchR antagonist, inhibits Ach binding and neurotransmission. Here we demonstrate biotinylated alpha-BTX, bound to native mouse ... More
Mechanochemical delivery and dynamic tracking of fluorescent quantum dots in the cytoplasm and nucleus of living cells.
AuthorsYum K, Na S, Xiang Y, Wang N, Yu MF,
JournalNano Lett
PubMed ID19366190
Studying molecular dynamics inside living cells is a major but highly rewarding challenge in cell biology. We present a nanoscale mechanochemical method to deliver fluorescent quantum dots (QDs) into living cells, using a membrane-penetrating nanoneedle. We demonstrate the selective delivery of monodispersed QDs into the cytoplasm and the nucleus of ... More
Detection of single quantum dots in model organisms with sheet illumination microscopy.
AuthorsFriedrich M, Nozadze R, Gan Q, Zelman-Femiak M, Ermolayev V, Wagner TU, Harms GS,
JournalBiochem Biophys Res Commun
PubMed ID19833091
Single-molecule detection and tracking is important for observing biomolecule interactions in the microenvironment. Here we report selective plane illumination microscopy (SPIM) with single-molecule detection in living organisms, which enables fast imaging and single-molecule tracking and optical penetration beyond 300 microm. We detected single nanocrystals in Drosophila larvae and zebrafish embryo. ... More
Wet electron microscopy with quantum dots.
AuthorsTimp W, Watson N, Sabban A, Zik O, Matsudaira P
JournalBiotechniques
PubMed ID16989089
Wet electron microscopy (EM) is a new imaging method with the potential to allow higher spatial resolution of samples. In contrast to most EM methods, it requires little time to perform and does not require complicated equipment or difficult steps. We used this method on a common murine macrophage cell ... More
NSOM/QD-based nanoscale immunofluorescence imaging of antigen-specific T-cell receptor responses during an in vivo clonal V{gamma}2V{delta}2 T-cell expansion.
AuthorsChen Y, Shao L, Ali Z, Cai J, Chen ZW,
JournalBlood
PubMed ID18039956
Nanoscale imaging of an in vivo antigen-specific T-cell immune response has not been reported. Here, the combined near-field scanning optical microscopy- and fluorescent quantum dot-based nanotechnology was used to perform immunofluorescence imaging of antigen-specific T-cell receptor (TCR) response in an in vivo model of clonal T-cell expansion. The near-field scanning ... More
Single particle quantum dot imaging achieves ultrasensitive detection capabilities for Western immunoblot analysis.
AuthorsScholl B, Liu HY, Long BR, McCarty OJ, O'Hare T, Druker BJ, Vu TQ,
JournalACS Nano
PubMed ID19453141
Substantially improved detection methods are needed to detect fractionated protein samples present at trace concentrations in complex, heterogeneous tissue and biofluid samples. Here we describe a modification of traditional Western immunoblotting using a technique to count quantum-dot-tagged proteins on optically transparent PVDF membranes. Counts of quantum-dot-tagged proteins on immunoblots achieved ... More
Time-resolved Förster-resonance-energy-transfer DNA assay on an active CMOS microarray.
AuthorsSchwartz DE, Gong P, Shepard KL,
JournalBiosens Bioelectron
PubMed ID18515059
We present an active oligonucleotide microarray platform for time-resolved Förster-resonance-energy-transfer (TR-FRET) assays. In these assays, immobilized probe is labeled with a donor fluorophore and analyte target is labeled with a fluorescence quencher. Changes in the fluorescence decay lifetime of the donor are measured to determine the extent of hybridization. In ... More
She3p binds to the rod of yeast myosin V and prevents it from dimerizing, forming a single-headed motor complex.
AuthorsHodges AR, Krementsova EB, Trybus KM,
JournalJ Biol Chem
PubMed ID18175803
Vertebrate myosin Va is a dimeric processive motor that walks on actin filaments to deliver cargo. In contrast, the two class V myosins in budding yeast, Myo2p and Myo4p, are non-processive (Reck-Peterson, S. L., Tyska, M. J., Novick, P. J., and Mooseker, M. S. (2001) J. Cell Biol. 153, 1121-1126). ... More
Suppression of quantum dot blinking in DTT-doped polymer films.
AuthorsAntelman J, Ebenstein Y, Dertinger T, Michalet X, Weiss S,
JournalJ Phys Chem C Nanomater Interfaces
PubMed ID20161096
In this report we evaluate the emission properties of single quantum dots embedded in a thin, thiol containing polymer film. We report the suppression of quantum dot blinking leading to a continuous photon flux from both organic and water soluble quantum dots and demonstrate their application as robust fluorescent point ... More
Semiautomated multiplexed quantum dot-based in situ hybridization and spectral deconvolution.
AuthorsByers RJ, Di Vizio D, O'connell F, Tholouli E, Levenson RM, Gossage K, Gossard K, Twomey D, Yang Y, Benedettini E, Rose J, Ligon KL, Finn SP, Golub TR, Loda M,
JournalJ Mol Diagn
PubMed ID17251332
Gene expression profiling has identified several potentially useful gene signatures for predicting outcome or for selecting targeted therapy. However, these signatures have been developed in fresh or frozen tissue, and there is a need to apply them to routinely processed samples. Here, we demonstrate the feasibility of a potentially high-throughput ... More
Virus-specific CD8+ T cells accumulate near sensory nerve endings in genital skin during subclinical HSV-2 reactivation.
AuthorsZhu J, Koelle DM, Cao J, Vazquez J, Huang ML, Hladik F, Wald A, Corey L,
JournalJ Exp Med
PubMed ID17325200
Cytotoxic CD8(+) T cells play a critical role in controlling herpes simplex virus (HSV) infection and reactivation. However, little is known about the spatiotemporal dynamics of CD8(+) T cells during HSV lesion evolution or about their involvement in immune surveillance after lesion resolution. Using quantum dot-conjugated peptide-major histocompatibility complex multimers, ... More
Quantum-dot-assisted characterization of microtubule rotations during cargo transport.
AuthorsNitzsche B, Ruhnow F, Diez S,
JournalNat Nanotechnol
PubMed ID18772917
Owing to their wide spectrum of in vivo functions, motor proteins, such as kinesin-1, show great potential for application as nanomachines in engineered environments. When attached to a substrate surface, these motors are envisioned to shuttle cargo that is bound to reconstituted microtubules--one component of the cell cytoskeleton--from one location ... More
Actin restricts FcepsilonRI diffusion and facilitates antigen-induced receptor immobilization.
AuthorsAndrews NL, Lidke KA, Pfeiffer JR, Burns AR, Wilson BS, Oliver JM, Lidke DS,
JournalNat Cell Biol
PubMed ID18641640
The actin cytoskeleton has been implicated in restricting diffusion of plasma membrane components. Here, simultaneous observations of quantum dot-labelled FcepsilonRI motion and GFP-tagged actin dynamics provide direct evidence that actin filament bundles define micron-sized domains that confine mobile receptors. Dynamic reorganization of actin structures occurs over seconds, making the location ... More
Identification of internalizing human single-chain antibodies targeting brain tumor sphere cells.
AuthorsZhu X, Bidlingmaier S, Hashizume R, James CD, Berger MS, Liu B,
JournalMol Cancer Ther
PubMed ID20587664
Glioblastoma multiforme (GBM) is the most common and aggressive form of primary brain tumor for which there is no curative treatment to date. Resistance to conventional therapies and tumor recurrence pose major challenges to treatment and management of this disease, and therefore new therapeutic strategies need to be developed. Previous ... More
Bioconjugation of quantum dot luminescent probes for Western blot analysis.
AuthorsMakrides SC, Gasbarro C, Bello JM
JournalBiotechniques
PubMed ID16235562
Western blot analysis is a widely used technique for protein immunodetection. Its current format, however is unsuitable for multiplex detection of proteins, primarily due to intrinsic limitations of standard organic dyes employed as probes. Quantum dot (QD) semiconductor nanoparticles exhibit significant advantages over organic dyes, including their broad absorption bands, ... More
Differential labeling of myosin V heads with quantum dots allows direct visualization of hand-over-hand processivity.
AuthorsWarshaw DM, Kennedy GG, Work SS, Krementsova EB, Beck S, Trybus KM
JournalBiophys J
PubMed ID15764654
The double-headed myosin V molecular motor carries intracellular cargo processively along actin tracks in a hand-over-hand manner. To test this hypothesis at the molecular level, we observed single myosin V molecules that were differentially labeled with quantum dots having different emission spectra so that the position of each head could ... More
Metabolic installation of thiols into sialic acid modulates adhesion and stem cell biology.
AuthorsSampathkumar SG, Li AV, Jones MB, Sun Z, Yarema KJ
JournalNat Chem Biol
PubMed ID16474386
Metabolic 'oligosaccharide engineering' methods based on N-acetyl-D-mannosamine (ManNAc) analogs allow the glycocalyx of living cells to be remodeled. Herein we report the analog Ac(5)ManNTGc (1) that enables thiols to be expressed in surface sialic acids. By locating this versatile functional group on the outer periphery of normally nonadhesive human Jurkat ... More
Bioconjugated quantum dots for multiplexed and quantitative immunohistochemistry.
AuthorsXing Y, Chaudry Q, Shen C, Kong KY, Zhau HE, Chung LW, Petros JA, O'Regan RM, Yezhelyev MV, Simons JW, Wang MD, Nie S
JournalNat Protoc
PubMed ID17546006
Bioconjugated quantum dots (QDs) provide a new class of biological labels for evaluating biomolecular signatures (biomarkers) on intact cells and tissue specimens. In particular, the use of multicolor QD probes in immunohistochemistry is considered one of the most important and clinically relevant applications. At present, however, clinical applications of QD-based ... More
Flow cytometric analysis of DNA binding and cleavage by cell surface-displayed homing endonucleases.
LAGLIDADG homing endonucleases (LHEs) cleave 18-24 bp DNA sequences and are promising enzymes for applications requiring sequence-specific DNA cleavage amongst genome-sized DNA backgrounds. Here, we report a method for cell surface display of LHEs, which facilitates analysis of their DNA binding and cleavage properties by flow cytometry. Cells expressing surface ... More
From the Cover: Detection of fractional steps in cargo movement by the collective operation of kinesin-1 motors.
AuthorsLeduc C, Ruhnow F, Howard J, Diez S
JournalProc Natl Acad Sci U S A
PubMed ID17569782
The stepping behavior of single kinesin-1 motor proteins has been studied in great detail. However, in cells, these motors often do not work alone but rather function in small groups when they transport cellular cargo. Until now, the cooperative interactions between motors in such groups were poorly understood. A fundamental ... More
Qdot nanocrystal conjugates conjugated to bombesin or ANG II label the cognate G protein-coupled receptor in living cells.
AuthorsYoung SH, Rozengurt E
JournalAm J Physiol Cell Physiol
PubMed ID16236822
Quantum dots (Qdot Nanocrystal Conjugates; Quantum Dot, Hayward, CA) exhibit high fluorescence and low photobleaching compared with organic dyes, properties that should enhance their detection at low densities. In view of the properties of Qdots and the biological and pharmaceutical importance of G protein-coupled receptors (GPCRs), we attempted to use ... More
Single molecule studies of quantum dot conjugates in a submicrometer fluidic channel.
A microfluidic and optical system was created for the detection and analysis of single molecules in solution. Fluidic channels with submicrometer dimensions were used to isolate, detect and identify individual quantum dots conjugated with organic fluorophores. The channels were fabricated in fused silica with a 500 nm square cross section. ... More
Qdot nanobarcodes for multiplexed gene expression analysis.
AuthorsEastman PS, Ruan W, Doctolero M, Nuttall R, de Feo G, Park JS, Chu JS, Cooke P, Gray JW, Li S, Chen FF
JournalNano Lett
PubMed ID16683851
We report a quantum dot (Qdot) nanobarcode-based microbead random array platform for accurate and reproducible gene expression profiling in a high-throughput and multiplexed format. Four different sizes of Qdots, with emissions at 525, 545, 565, and 585 nm are mixed with a polymer and coated onto the 8-mum-diameter magnetic microbeads ... More
Multispectral imaging of clinically relevant cellular targets in tonsil and lymphoid tissue using semiconductor quantum dots.
AuthorsFountaine TJ, Wincovitch SM, Geho DH, Garfield SH, Pittaluga S
JournalMod Pathol
PubMed ID16778828
Determination of the expression and spatial distribution of molecular epitopes, or antigens, in patient tissue specimens has substantially improved the pathologist's ability to classify disease processes. Certain disease pathophysiologies are marked by characteristic increased or decreased expression of developmentally controlled antigens, defined as Cluster of Differentiation markers, that currently form ... More
Optical imaging of cervical pre-cancers with structured illumination: an integrated approach.
AuthorsRahman M, Abd-El-Barr M, Mack V, Tkaczyk T, Sokolov K, Richards-Kortum R, Descour M
JournalGynecol Oncol
PubMed ID16154624
OBJECTIVE: Structured illumination microscopy is an inexpensive alternative to confocal microscopy that allows optical sectioning at a sub-cellular resolution. However, its application in imaging biological tissue has been limited by inadequate contrast present in them especially in reflectance imaging. Novel, optically active contrast agents like gold nanoparticles and quantum dots ... More