CD Bioparticles provides PbS/CdS near infrared (NIR) quantum dots ranging in narrow band fluorescent emission wavelengths from 850 nm to 1450 nm. These core/shell QDs have higher quantum yields (are brighter) and have greater wavelength stability relative to the core only PbS quantum dots that are commercially available. CdS shell growth generally decreases the photoluminescence quantum yield of PbS/CdS core/shell QDs as compared to PbS core QDs. This suggests that photoluminescence quenching is mainly caused by defects at the PbS/CdS interface. PbS/CdS QDs are widely used in highly sensitive cellular imaging, photovoltaic devices, solar cells, light emitting devices, etc.