Development of homogeneous binding assays based on fluorescence resonance energy transfer between quantum dots and Alexa Fluor fluorophores.
AuthorsNikiforov TT, Beechem JM
JournalAnal Biochem
PubMed ID16860286
'We studied the fluorescence resonance energy transfer (FRET) between quantum dots emitting at 565, 605, and 655 nm as energy donors and Alexa Fluor fluorophores with absorbance maxima at 594, 633, 647, and 680 nm as energy acceptors. As a first step, we prepared covalent conjugates between all three types ... More
Targeted quantum dot conjugates for siRNA delivery.
AuthorsDerfus AM, Chen AA, Min DH, Ruoslahti E, Bhatia SN
JournalBioconjug Chem
PubMed ID17630789
'Treatment of human diseases such as cancer generally involves the sequential use of diagnostic tools and therapeutic modalities. Multifunctional platforms combining therapeutic and diagnostic imaging functions in a single vehicle promise to change this paradigm. in particular, nanoparticle-based multifunctional platforms offer the potential to improve the pharmacokinetics of drug formulations, ... More
Specific and covalent labeling of a membrane protein with organic fluorochromes and quantum dots.
AuthorsBonasio R, Carman CV, Kim E, Sage PT, Love KR, Mempel TR, Springer TA, von Andrian UH
JournalProc Natl Acad Sci U S A
PubMed ID17785425
'The real-time observation of protein dynamics in living cells and organisms is of fundamental importance for understanding biological processes. Most approaches to labeling proteins exploit noncovalent interactions, unsuitable to long-term studies, or genetic fusion to naturally occurring fluorescent proteins that often have unsatisfactory optical properties. Here we used the fungal ... More
Optimizing a waveguide-based sandwich immunoassay for tumor biomarkers: evaluating fluorescent labels and functional surfaces.
AuthorsMukundan H, Xie H, Anderson AS, Grace WK, Shively JE, Swanson BI,
JournalBioconjug Chem
PubMed ID19173652
'The sensor team at the Los Alamos National Laboratory has developed a waveguide-based optical biosensor for the detection of biomarkers associated with disease. We have previously demonstrated the application of this technology to the sensitive detection of carcinoembryonic antigen in serum and nipple aspirate fluid from breast cancer patients. In ... More
Quantum dot targeting with lipoic acid ligase and HaloTag for single-molecule imaging on living cells.
AuthorsLiu DS, Phipps WS, Loh KH, Howarth M, Ting AY,
JournalACS Nano
PubMed ID23181687
'We present a methodology for targeting quantum dots to specific proteins on living cells in two steps. In the first step, Escherichia coli lipoic acid ligase (LplA) site-specifically attaches 10-bromodecanoic acid onto a 13 amino acid recognition sequence that is genetically fused to a protein of interest. In the second ... More
Self-controlled monofunctionalization of quantum dots for multiplexed protein tracking in live cells.
AuthorsYou C, Wilmes S, Beutel O, Löchte S, Podoplelowa Y, Roder F, Richter C, Seine T, Schaible D, Uzé G, Clarke S, Pinaud F, Dahan M, Piehler J,
JournalAngew Chem Int Ed Engl
PubMed ID20432494
'Most approaches for targeting proteins using QDs in live cells are based on biotin–streptavidin interactions, which form quasi-irreversible complexes. For multiplexed, generic labeling of proteins on the cell surface, further targeting strategies are required. We have recently described tris(hydroxymethyl)methylamine–nitrilotriacetic acid (Tris-NTA) moieties for highly specific and stable attachment of fluorophores ... More
Fluorescence fluctuations of quantum-dot sensors capture intracellular protein interaction dynamics.
AuthorsZamir E, Lommerse PH, Kinkhabwala A, Grecco HE, Bastiaens PI,
JournalNat Methods
PubMed ID20228813
We extend the in vitro principle of co-immunoprecipitation to quantify dynamic protein interactions in living cells. Using a multiresolution implementation of fluorescence correlation spectroscopy to achieve maximal temporal resolution, we monitored the interactions of endogenous bait proteins, recruited by quantum dots, with fluorescently tagged prey. With this approach, we analyzed ... More
Real-time imaging of astrocyte response to quantum dots: in vivo screening model system for biocompatibility of nanoparticles.
AuthorsMaysinger D, Behrendt M, Lalancette-Hébert M, Kriz J
JournalNano Lett
PubMed ID17638392
Astrocytes are the principle macroglial brain cells. They are activated by different stressors and brain injuries. Quantum dots (QDs) can cause oxidative stress. This study shows a real-time imaging of primary cortical cultures and assessment of QD-induced activation of astrocytes in the brains of transgenic mice with the luciferase gene ... More
Variables influencing interactions of untargeted quantum dot nanoparticles with skin cells and identification of biochemical modulators.
AuthorsRyman-Rasmussen JP, Riviere JE, Monteiro-Riviere NA
JournalNano Lett
PubMed ID17408303
Skin cells (NHEK) take up untargeted quantum dots (QD) with surface polyethylene glycol (PEG), amines, and carboxylic acids, but the mechanisms are unknown. Time courses of QD-NHEK interactions were determined and effects of QD surface coating, temperature, culture medium supplements and inhibitors of the cell cycle and endocytosis identified. The ... More
Sentinel lymph node imaging using quantum dots in mouse tumor models.
We demonstrate that quantum dots injected into two model tumors rapidly migrate to sentinel lymph nodes. PEG-coated quantum dots having terminal carboxyl, amino, or methoxyl groups all migrated from the tumor to surrounding lymph nodes similarly. Passage from the tumor through lymphatics to adjacent nodes could be visualized dynamically through ... More
Ligand-functionalized nanoparticles target endothelial cells in retinal capillaries after systemic application.
AuthorsPollinger K, Hennig R, Ohlmann A, Fuchshofer R, Wenzel R, Breunig M, Tessmar J, Tamm ER, Goepferich A,
JournalProc Natl Acad Sci U S A
PubMed ID23530216
To date, diseases affecting vascular structures in the posterior eye are mostly treated by laser photocoagulation and multiple intraocular injections, procedures that destroy healthy tissue and can cause vision-threatening complications. To overcome these drawbacks, we investigate the feasibility of receptor-mediated nanoparticle targeting to capillary endothelial cells in the retina after ... More
Redistribution of actin during assembly and reassembly of the contractile ring in grasshopper spermatocytes.
AuthorsAlsop GB, Chen W, Foss M, Tseng KF, Zhang D,
JournalPLoS One
PubMed ID19287500
Cytokinesis in animal cells requires the assembly of an actomyosin contractile ring to cleave the cell. The ring is highly dynamic; it assembles and disassembles during each cell cleavage, resulting in the recurrent redistribution of actin. To investigate this process in grasshopper spermatocytes, we mechanically manipulated the spindle to induce ... More
Dynamics and mechanisms of quantum dot nanoparticle cellular uptake.
AuthorsXiao Y, Forry SP, Gao X, Holbrook RD, Telford WG, Tona A,
JournalJ Nanobiotechnology
PubMed ID20550705
ABSTRACT: BACKGROUND: The rapid growth of the nanotechnology industry and the wide application of various nanomaterials have raised concerns over their impact on the environment and human health. Yet little is known about the mechanism of cellular uptake and cytotoxicity of nanoparticles. An array of nanomaterials has recently been introduced ... More
Mechanisms of quantum dot nanoparticle cellular uptake.
AuthorsZhang LW, Monteiro-Riviere NA,
JournalToxicol Sci
PubMed ID19414515
Due to the superior photoemission and photostability characteristics, quantum dots (QD) are novel tools in biological and medical applications. However, the toxicity and mechanism of QD uptake are poorly understood. QD nanoparticles with an emission wavelength of 655 nm are ellipsoid in shape and consist of a cadmium/selenide core with ... More
Optical coding of mammalian cells using semiconductor quantum dots.
AuthorsMattheakis LC, Dias JM, Choi YJ, Gong J, Bruchez MP, Liu J, Wang E
JournalAnal Biochem
PubMed ID15051536
Cell-based assays are widely used to screen compounds and study complex phenotypes. Few methods exist, however, for multiplexing cellular assays or labeling individual cells in a mixed cell population. We developed a generic encoding method for cells that is based on peptide-mediated delivery of quantum dots (QDs) into live cells. ... More
Surface coatings determine cytotoxicity and irritation potential of quantum dot nanoparticles in epidermal keratinocytes.
AuthorsRyman-Rasmussen JP, Riviere JE, Monteiro-Riviere NA
JournalJ Invest Dermatol
PubMed ID16902417
Quantum dot (QD) nanoparticles have potential applications in nanomedicine as drug delivery vectors and diagnostic agents, but the skin toxicity and irritation potential of QDs are unknown. Human epidermal keratinocytes (HEKs) were used to assess if QDs with different surface coatings would cause differential effects on HEK cytotoxicity, proinflammatory cytokine ... More
Penetration of intact skin by quantum dots with diverse physicochemical properties.
AuthorsRyman-Rasmussen JP, Riviere JE, Monteiro-Riviere NA
JournalToxicol Sci
PubMed ID16443688
Skin is the largest organ of the body and is a potential route of exposure to engineered nanomaterials, but the permeability of the skin to these nanomaterials is unknown. We selected commercially available quantum dots (QD) of two core/shell sizes and shapes and three different surface coatings to determine if ... More