Labeling of BSA and imaging of mouse T-lymphocyte as well as mouse spleen tissue by L-glutathione capped CdTe quantum dots.

L-glutathione capped highly fluorescent CdTe quantum dots (QDs) were prepared by an aqueous approach and used as fluorescent labels to link albumin bovine serum (BSA) and rat anti-mouse CD4, which was expressed on mouse T-lymphocyte and mouse spleen tissue. The sharp and narrow emission peaks showed that the as-prepared QDs have desirable dispersibility, uniformity and good fluorescence properties. Both CdTe-BSA and CdTe-CD4 conjugates showed an enhancement of fluorescence intensity over that of bare CdTe QDs. The experimental result of gel electrophoresis confirmed the successful conjugation of CdTe-BSA and CdTe-CD4. The fluorescent microscopic images of CdTe-CD4 labeled mouse T-lymphocyte cells and mouse spleen tissue were compared with that obtained from fluorescein isothiocyanate labeling. It was demonstrated that the CdTe QDs-based probe exhibited much better photostability and fluorescence intensity than fluorescein isothiocyanate, showing a good application potential in the immuno-labeling of cells and tissues.