Quantum Dots Synthesis and Bioconjugation
Quantum dots (QDs) are a novel class of inorganic fluorophore which are gaining widespread recognition as a result of their exceptional photophysical properties. They are extremely small, typically measuring only a few nanometers in size, and have unique electronic and optical properties. They are rapidly being applied to existing and emerging technologies, and could have an important role in many areas. Based on the elaborate chemical synthesis platform and experienced chemical experts, BOC Sciences provides comprehensive quantum dots synthesis and bioconjugation services.
Physico-chemical properties of quantum dots
Quantum dots exhibit unique optical properties due to confinement of electron hole pairs (excitons) within the grain boundary of the nanocrystals. These unique photo-physical properties of QDs make them suitable for wide range of biomedical applications such as drug delivery, gene therapy etc.
- Size tunable light emission
- Composition tunable light emission
- Broad absorption spectra and size tunable narrow emission spectra
- Enormous absorption extinction coefficients
- High fluorescent quantum yields
- Photo chemically robust
- Resistant to photo bleaching
- Shows fluorescence intermittency
- Large stokes shift
Applications of quantum dots
Quantum dot labels have been successfully used for a variety of bioanalytical purposes, such as DNA hybridization detection, immunoassays, and binding assays using fluorescence resonant energy transfer (FRET) to probe for target events.
- In vitro Imaging
- In vivo Imaging
- Photodynamic therapy
- Pathogen and toxin detection
- Gene delivery
- QDs in therapeutics and diagnostics
- Tumour biology investigation
- Cell tracking
QDs as theranostics agent (V.G. Reshma. et al. 2018)
Our services
- Chemical synthesis quantum dot
QD synthesis can be tailored to specific requirements, with core, shell and coating characteristics all affecting photochemical properties.
- Quantum dot bioconjugation
Use of a bifunctional ligand such as mercaptoacetic acid for linking QDs to biomolecules.
TOPO-capped QDs bound to a modified acrylic acid polymer by hydrophobic forces.
QD solubilisation and bioconjugation using a mercaptosilane compound.
Positively charged biomolecules linked to negatively charged QDs by electrostatic attraction.
Incorporation of QDs into microbeads and nanobeads
- Using nuclear magnetic resonance spectroscopy and X-ray photoelectron spectroscopy to characterize the QD surface properties
A schematic illustrating different approaches of conjugation of QDs to biomolecules (Jamieson T. et al. 2007)
Our advantages
- Quantum dots may be manufactured with diameters from a few nanometers to a few micrometers
- Size distribution can be controlled within 2% using precise growth techniques, involving high annealing temperatures.
- Better choice of shell and coating
- Good biocompatibility
- Long-term stability
Recent advances have shown that nanometer-sized semiconductor particles can be covalently linked with biorecognition molecules such as peptides, antibodies, nucleic acids, or small-molecule ligands for use as biological labels. High-quality QDs are also well suited for optical encoding and multiplexing applications due to their broad excitation profiles and narrow/symmetric emission spectra. We can provide high-quality quantum dots for your projects.