Photoluminescence of bioconjugated core-shell $CdSe∕ZnS$ quantum dots

This article presents the analysis of photoluminescence (PL) spectra of $CdSe∕ZnS$ quantum dots (QDs) with and without bioconjugation to biomolecules, Interleukin 10 (IL10) antibodies. Commercial $CdSe∕ZnS$ QDs used in the study are characterized by the color emission with the maximum at $605nm$ $(2.05eV)$⁠. It is shown that PL spectra of nonconjugated QDs can be presented as a superposition of PL bands dealing with exciton emission in the CdSe core and electron-hole emission via defect states at the $CdSe∕ZnS$ interface. The comparison of PL spectra of such type of $CdSe∕ZnS$ QDs with and without bioconjugation gives the opportunity to detect the bioconjugation without mistake. Moreover the electrostatic mechanism of bioconjugation process follows from the analyses of PL spectra of $CdSe∕ZnS$ QDs.