NSTC- Supplier of quantum dots, CdTe Quantum Dots

Quantum Dots:-

Luminescent inorganic nanocrystals (Q-dots). The emission wavelength is a function of the crystal size -crystals of the same chemistry can have the emission maxima in a wide range. CdTe hydrophilic Q-dots are coated with -COOH groups and can be easily used for labeling purposes forchemical and biological applications.CdSe/ZnS and ZnCdSe/ZnS (core/shell type) Q-dotsare hydrophobic and are soluble in most non-polar organic solvents.

CdTe Quantum Dots, powder, hydrophilic

Easily forms colloidal solutions in water. Terminated with -COOH group.Ideal for labeling purposes. Coupling with -NH₂ groups can be achieved through
EDC-mediated esterefication.

General labeling procedure for proteins :-

(adopted from Wang et al. Nanoletters 2002, vol. 2, No. 8, 817-822):
Reaction mixture containing 0.1 µM/mL CdTe quantum dots, 2 mg/mL protein, 1 mg/ mL sulfo-NHS (CAS# 106627-54-7), 10 mg/mL EDC (CAS# 25952-53-8) in pH 7.0 PBS buffer is prepared and stored for 2-4 h at room temperature and then stored at 4°C overnight.
The precipitate (unconjugated Q-dots) if any is removed by centrifugation. The stock of ready-to-use product should be stored at 4°C. Optionally it can be dyalized on a membrane with MWCO of 12000-14000 against pH 7.0 PBS buffer and stored at 4°C.
Emission wavelength may slightly shift after labeling procedure.

510 ± 5 nm λ emission maximum. Particles molar weight ca. 3200 g/mol