Research / 2018 / Article / Fig 2

Research Article

A Simple Approach to Bioconjugation at Diverse Levels: Metal-Free Click Reactions of Activated Alkynes with Native Groups of Biotargets without Prefunctionalization

Figure 2

Schematic illustration for metal-free amino-yne click bioconjugation between chitosan and PEG with fluorescent activated alkynes. (a) Functionalization of natural polymers via the amino-yne click reaction. (b) Photographs of chitosan, Chit-TPA, and Chit-TPE in the presence of UV irradiation or not. (c) Synthetic rout of PEGylation of triphenylamine (TPA) via the amino-yne click reaction. (d) Hydrodynamic diameter distribution and TEM image (inset) determined for the aqueous dispersion of PEG-TPA. (e) Fluorescent emission spectrum of PEG-TPA aqueous dispersion (= 405 nm, insert photographs: the water dispersion under white light and UV irradiation). (f) CLSM images of EMT-6 cells upon incubating with the aqueous dispersion of PEG-TPA at 5 μM for 4 h and cell nucleus were costained with Red dot1.