Quantum barcode

The absorption and emission properties of organic dyes are generally tuned by altering the substitution pattern. However, tuning the fluorescence lifetimes over a range of several 10 ns while barely affecting the spectral features and maintaining a moderate fluorescence quantum yield is challenging. Such properties are required for lifetime multiplexing and barcoding applications. Here, we show how this can be achieved for the class of fluoranthene dyes, which have substitution-dependent lifetimes between 6 and 33 ns for single wavelength excitation and emission...

Protein drugs showing strong pharmaceutical activity, high specificity, and low toxicity and side effects have drawn extensive attention in the field of life sciences and medicine. Precise evaluation of the function of these drugs requires accurate and sensitive detection methods. Here, we report a novel chromatography-tandem mass spectrometry (LC-MS/MS) method for sensitive and selective detection of protein drugs. Magnetic nanoparticles (Apt29@MNPs) were functionalized by thrombin aptamers, and quantum dots (Apt15@ss@QDs) were dual-functionalized with quantitative thrombin aptamers and small molecules with high ionization efficiency as the mass barcode...

Lanthanide(III) ions (Ln3+ ) in coordination compounds exhibit unique luminescence properties with narrow and characteristic f-f transitions throughout the visible and near-infrared (NIR) ranges. In addition, some Ln3+ such as Pr3+ , Sm3+ , Dy3+ , Ho3+ , Er3+ , and Tm3+ possess an exceptional ability, although less explored, to exhibit dual-range emissions. Such remarkable features allow highly specific use in materials science and biology, for example, for the creation of sophisticated barcode modules or for the next generation of optical imaging applications...

Next generation life science technologies will require the integration of building blocks with tunable physical and chemical architectures at the microscale. A central issue is to govern the multidimensional anisotropic space that defines these microparticle attributes. However, this control is limited to one or few dimensions due to profound fabrication tradeoffs, a problem that is exacerbated by miniaturization. Here, a vast number of anisotropic dimensions are integrated combining SU-8 photolithography with (bio)chemical modifications via soft-lithography...

Single-cell omics provide insight into cellular heterogeneity and function. Recent technological advances have accelerated single-cell analyses, but workflows remain expensive and complex. We present a method enabling simultaneous, ultra-high throughput single-cell barcoding of millions of cells for targeted analysis of proteins and RNAs. Quantum barcoding (QBC) avoids isolation of single cells by building cell-specific oligo barcodes dynamically within each cell. With minimal instrumentation (four 96-well plates and a multichannel pipette), cell-specific codes are added to each tagged molecule within cells through sequential rounds of classical split-pool synthesis...

The development of a powerful immunoassay platform with capacities of both simplicity and high multiplexing is promising for disease diagnosis. To meet this urgent need, for the first time, a multiplexed luminescent oxygen channeling immunoassay (multi-LOCI) platform by implementation of LOCI with suspension array technology is reported. As the microcarrier of the platform, a unique dual-functional barcode with a host-guest structure composed of a quantum dot host bead (QDH) and LOCI acceptor beads (ABs) is designed, in which QDH provides function of high coding capacity while ABs facilitate the LOCI function...

In this study, fluorescence-encoded magnetic biocompatible nanoparticles (NPs) were constructed from CdSe@ZnS quantum dots (QDs) and Fe3O4 nanoparticles with a one-step reprecipitation-encapsulation method. The resultant hybrid NPs exhibit small size (∼130 nm in diameter), high brightness of QDs, two color emissions (green and red) under single-wavelength excitation, easy separation with a magnet and efficient cellular internalization. Energy transfer between the incorporated QDs was studied to better tailor the encoded fluorescence, and 11 barcodes were obtained by adjusting the ratio of green and red QDs...

Semiconductor quantum dots (QDs) are the most versatile fluorophores for Förster resonance energy transfer (FRET) because they can function as both donors and acceptors for a multitude of fluorophores. However, a complete understanding of multidonor-multiacceptor FRET networks on QDs and their full employment into advanced fluorescence sensing and imaging have not been accomplished. Here, we provide a holistic photophysical analysis of such multidonor-QD-multiacceptor FRET systems using time-resolved and steady-state photoluminescence (PL) spectroscopy and Monte Carlo simulations...

Purpose: Projects evaluating the effects of radiation, within the National Institutes of Quantum and Radiological Science and Technology (QST), National Institute of Radiological Sciences (NIRS), have focused on risk analyses for life shortening and cancer prevalence using laboratory animals. Genetic and epigenetic alterations in radiation-induced tumors have been also analyzed, with the aim of better understanding mechanisms of radiation carcinogenesis. As well as the economic and practical limitations of repeating such large-scale experiments, ethical considerations make it vital that we store and share the pathological data and samples of the animal experiments for future use...

The aim of this work was to use the yeast Saccharomyces cerevisiae as a tool for toxicogenomic studies of Engineered Nanomaterials (ENMs) risk assessment, in particular focusing on cadmium based quantum dots (CdS QDs). This model has been exploited for its peculiar features: a short replication time, growth on both fermentable and oxidizable carbon sources, and for the contextual availability of genome wide information in the form of genetic maps, DNA microarray, and collections of barcoded mutants. The comparison of the whole genome analysis with the microarray experiments (99...

As a new class of two-dimensional (2D) materials, molybdenum disulfide (MoS2 ) has huge potential in biomedical area; while its applications in multiplex bioassays are still a challenge. Here, we present novel MoS2 -integrated silica colloidal crystal barcode (SCCB) for multiplex microRNA (miRNA) screening. MoS2 was adsorbed on SCCBs by electrostatic interaction, and quantum dots (QDs) decorated hairpin probes were coupled on MoS2 by covalent linkage. As the MoS2 could quench the QDs of the hairpin probes, they together formed a molecular beacon (MB) structure before the detection...

Members of the Brucella spp. are facultative intracellular bacteria that can cause global brucellosis, a zoonotic disease. Herein, a novel fluorescence signal amplification (FSA) method for the rapid detection of B. melitensis 16M was developed based on peptide-mediated magnetic separation (PMS) technology and Au nanoparticle (AuNP)-mediated bio-barcode assay technology assembled by quantum dots (QDs). The PMS technology was used to specifically capture and isolate B. melitensis 16M from food. The immunomagnetic bead-B...

An electrochemiluminescence (ECL) based method is described for the determination of the activity of the enzyme uracil-DNA glycosylase (UDG). It is based on the use of nicking enzyme-assisted signal amplification and catalytic hairpin assembly. UDG can recognize and hydrolyze the uracil bases from the stem of hairpin DNA1 (HP1). This causes the opening of HP1 to form a straight strand DNA. The straight HP1 can hybridize with hairpin DNA2 (HP2) to form a DNA duplex. In the presence of nicking enzyme, it can recognize and cut the specific sequences in the HP2 of the DNA duplex, and a subsequent release of HP1...

Fluorescence barcoding based on nanoparticles provides many advantages for multiparameter imaging. However, creating different concentration-independent codes without mixing various nanoparticles and by using single-wavelength excitation and emission for multiplexed cellular imaging is extremely challenging. Herein, we report the development of quantum dots (QDs) with two different SiO2 shell thicknesses (6 and 12 nm) that are coated with two different lanthanide complexes (Tb and Eu). FRET from the Tb or Eu donors to the QD acceptors resulted in four distinct photoluminescence (PL) decays, which were encoded by simple time-gated (TG) PL intensity detection in three individual temporal detection windows...

Metal-free organic phosphorescence materials are of imperious demands in optoelectronics and bioelectronics. However, it is still a formidable challenge to develop a material with simultaneous efficiency and lifetime enhancement under ambient conditions. In this study, we design and synthesize a new class of high efficient ultralong organic phosphorescence (UOP) materials through self-assembly of melamine and aromatic acids in aqueous media. A supramolecular framework can be formed via multiple intermolecular interactions, building a rigid environment to lock the molecules firmly in a three-dimensional network, which not only effectively limits the nonradiative decay of the triplet excitons but also promotes the intersystem crossing...

With the increasing demands for high-throughput multiplexed bioassays, quantum dot (QD)-encoded microbeads as biocarriers for various bioreactions have attracted considerable attention. However, three key requirements for these biocarriers are still longstanding issues: a stable fluorescence intensity, a large encoding capacity and abundant surface functional groups. Here, a novel one-pot strategy is developed, generating functionalized QD-encoded microspheres with a strong fluorescence intensity and optical stability...

Nowadays, fast and sensitive methods for biomarkers detection exist, but the performance of most of them still rely in centralized laboratory testing. The development of small, fast and simple to use medical device that can help in making diagnosis accurate and with low-invasiveness is now a major challenge for nanotechnology. To develop diagnostic devices for cancer detection, nanomaterials-based systems have significant advantages over current conventional approaches in terms of simplicity, sensitivity, specificity and rapidity...

Fluorescent polymer nanoparticles for long-term labeling and tracking of living cells with any desired color code are developed. They are built from biodegradable poly(lactic-co-glycolic acid) polymer loaded with cyanine dyes (DiO, DiI, and DiD) with the help of bulky fluorinated counterions, which minimize aggregation-caused quenching. At the single particle level, these particles are ≈20-fold brighter than quantum dots of similar color. Due to their identical 40 nm size and surface properties, these nanoparticles are endocytosed equally well by living cells...

Understanding of the mechanisms by which systemically administered nanoparticles achieve delivery across biological barriers remains incomplete, due in part to the challenge of tracking nanoparticle fate in the body. Here, we develop a new approach for "barcoding" nanoparticles composed of poly(lactic-co-glycolic acid) (PLGA) with bright, spectrally defined quantum dots (QDs) to enable direct, fluorescent detection of nanoparticle fate with subcellular resolution. We show that QD labeling does not affect major biophysical properties of nanoparticles or their interaction with cells and tissues...

Staphylococcus aureus, methicillin-resistant Staphylococcus aureus and Klebsiella pneumoniae are the most representative bacteria causing infectious diseases. Due to the increased application of antibiotics, the bacterial resistance is growing causing severe complications. Therefore, a sensitive determination of these pathogens is crucial for effective treatment. The aim of this study was to design an effective method for multiplex detection of Staphylococcus aureus, methicillin-resistant Staphylococcus aureus and Klebsiella pneumoniae taking advantage from properties of magnetic particles as well as fluorescent nanoparticles (quantum dots)...