BSA-drug-ZnO-PEI conjugates interaction with glycans of gp60 endothelial cell receptor protein for targeted drug delivery: a comprehensive spectroscopic study

The zinc oxide (ZnO) nanoparticles (NPs) have several biomedical applications such as drug delivery, bio-imaging, and biomedical research. ZnO NPs were remedied with polyethyleneimine (PEI) and modified with bovine serum albumin (BSA). Two anticancer drugs - Cisplatin (CIS) and Gemcitabine (GEM) were used in conjugation with BSA. BSA-ZnO-PEI (conjugate 1), BSA-CIS-ZnO-PEI (conjugate 2), and BSA-GEM-ZnO-PEI (conjugate 3) can be used for targeted drug delivery via glycans - N-acetylneuraminic acid (NANA), L-fucose (FUC), N-acetyl glucosamine (NAG), D-mannose (MAN), and D-galactose (GAL), of albumin binding membrane receptor protein (gp60). Considerable interaction and the strong binding of conjugate 2 and conjugate 3 with NANA were observed by UV-visible absorption and fluorescence spectra. The electrostatic stability of conjugate 2 and conjugate 3 with NANA was considerably increased in comparison to conjugate 1 as evident with zeta potential values. The fluorescence quenching data (Ksv and kq) and binding parameters (K and n) of BSA-CIS, BSA-GEM, conjugate 2, and conjugate 3 with NANA and FUC attributes to the strong binding. Amide I and amide III bands of the Raman signal suggested insignificant loss in alpha-helical and beta-sheet content of conjugate 2 and conjugate 3 with NANA and FUC. Therefore, the present study is going to assist in the comprehensive development of conjugates for targeted drug delivery based on the differential glycation pattern of gp60 protein. Communicated by Ramaswamy H. Sarma