AbstractThe paper presents the results of PL spectrum analysis of CdSe/ZnS QDs covered by PEG polymer with and without bioconjugation to bio-molecules .– the Osteopontin antibodies. Commercial CdSe/ZnS QDs used in the study are characterized by the color emission with the maximum at 640 nm (1.96 eV) at 300K. It is shown that PL spectra of nonconjugated QDs can be presented as a superposition of PL bands related to exciton emission in the CdSe core (1.96 eV) and some high energy PL bands (in the spectral range 2.37 .– 3.00 eV). The comparative study of PL spectrum at high (300K) and low (10K) temperatures has testified that high energy PL bands deal with electronhole emission via interface states at the CdSe/ZnS/polymer interfaces.It is revealed that the QD bioconjugation to the anti Osteopontin antibody is accompanied by the change dramatically in PL spectra. Main features of PL spectrum transformstions deal with decreasing the PL intensity of interface related PL bands and the rise of intensity of CdSe core related PL bands. The explanation of mentioned effects has been proposed on the base of re-charging of interface related states at the bioconjugation process.
Stable green and red dual-color emission in all-inorganic halide-mixed perovskite single microsheets
