Quantum dots (QDs) are semiconductor nanoparticles which exhibit size and composition-dependent optical and electronic (optoelectronic) properties. QDs are ultrasmall, typically falling in the size range between 1.5 and 10.0 nm. QDs are new types of fluorescent materials for biological labeling. CdSe quantum dots are produced by simultaneously injecting cadmium (Cd) and selenium (Se) precursor solutions into a heated growth solution of octadecene in ambient atmosphere. Once combined, Se and Cd form CdSe clusters that become continually growing QDs as the reaction progresses.

What are CdSe quantum dots used for?
Because of excellent size-dependent optical characteristics and chemical treatability, semiconducting CdSe quantum dots have been widely applied in biological identification (medical diagnosis), solar cells, optoelectronic devices, display instruments, nonlinear optical equipment, and magnetic materials.

How do you synthesize CdSe quantum dots?
The CdSe QDs can be synthesized by adding 10 ml Se precursor solution to the 48 mL Cd precursor solution, under N2 protection and magnetic stirring. The reactions were carried out at 50°C, 70°C, and 90°C for 5 min, 10 min, 15 min, 20 min, and 25 min, respectively.

Is CdSe toxic?
Due to the presence of Cd2+ ions in QDs, they are highly toxic (5, 13). In recent years, cytotoxicity of these particles has been considered highly due to their use in medical field. Also the cytotoxicity of CdSe QD in embryonic development was significantly reduced by the addition of a ZnS coating.

What are CdSe nanoparticles?
CdSe-derived nanoparticles smaller than 10 nm in size exhibit a characteristic called quantum confinement. Quantum confinement is related to size, which means that the properties of CdSe nanoparticles can be adjusted according to their size. One type of CdSe nanoparticles is a CdSe quantum dot.

CdSe quantum dots for science research?
CD Bioparticles provides CdSe semiconductor quantum dots with size-dependent emission range. Our CdSe quantum dots are core type II–VI semiconductor materials with size dependent optical/electronic properties, uniform size distribution and high quantum yield. The outer surface coating of organic ligands of CdSe quantum dots can be changed by ligand exchange process.

Various products are available at CD Bioparticles, such as the DiagNano™ CdSe Quantum Dots, 525 nm, DiagNano™ CdSe Quantum Dots, 600 nm, and DiagNano™ Octadecylamine CdSe Quantum Dots, 645-670 nm. These CdSe quantum dots can be used in highly sensitive cellular imaging, drug delivery and light emitting devices.

Author's Bio: 

CD Bioparticles is a leading manufacturer and supplier of various nanoparticles, microparticles and their coatings for R&D and commercialization in a wide variety of application areas including in-vitro diagnostics, biochemistry, cellular analysis, cell separation, immunoassay.