Surface modification of cyclomatrix polyphosphazene microsphere by thiol-ene chemistry and lectin recognition

• Published in: Applied surface science 2016-11, Vol.387, p.1029-1036
• Main Authors: Chen, Chen, Zhu, Xue-yan, Gao, Qiao-ling, Fang, Fei, Huang, Xiao-jun
• Format: Article
• Language: English
• Subjects: Chemical reactions; Concanavalin A; Crosslinking; Enzymes; Fourier transforms; Microsphere; Microspheres; Polyphosphazene; Polyphosphazenes; Thermal properties; Thiol-ene
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2016.06.116

A new synthetic route leading to polyphosphazene cyclomatrix microsphere with various functional groups has achieved via thiol-ene click modification. Herein, hexacholorocyclophosphazene (HCCP) crosslinked with bisphenol-S and 4,4′-diallyl bisphenol-S to generate broadly dispersed microspheres. Thiol-ene modification under UV irradiation not only presented high efficiency and flexibility for post-functionalization, but also imposed no harm on global morphology and crosslinked skeleton of such microspheres. [Display omitted] •Functional polyphosphazene microspheres with high chemical flexibility were synthesized by thiol-ene modification.•Polyphosphazene microspheres possessed high thermal stability.•Glycosylated polyphosphazene microspheres showed affinity to lectin Con-A, which inferred potential application in biomedicine. A new synthetic route leading to functional polyphosphazene cyclomatrix microsphere has been developed via thiol-ene click modification. Hexacholorocyclophosphazene (HCCP) was crosslinked with both bisphenol-S and 4,4′-diallyl bisphenol-S to obtain vinyl polyphosphazene microspheres (VPZM) in order to ensure high crosslinking degree and introduce vinyl moieties. Compared to the microspheres obtained by HCCP and bisphenol-S, the size of VPZM was broadly dispersed from 400nm to 1.40μm. Thiol-ene click reactions were carried out to attach functional groups, such as glucosyl, carboxyl, ester and dodecyl groups onto polyphosphazene microspheres, which demonstrated no change in morphology and size after modification. Solid state NMR (SSNMR) and Fourier transform infrared spectoscopy (FT-IR) results showed that the vinyl moieties were introduced in the period of crosslinking and functionalization was also successful via click reactions. Moreover, the microspheres presented a little difference in thermal properties after modification. Concanavalin A (Con-A) fluorescent adsorption was also observed for glucosyl microspheres. Thus, the thiol-ene modified polyphosphazene microspheres displayed chemical flexibility in post-functionalization. These microspheres can be potentially applicated in enzyme immobilization, protein adsorption and chromatographic separation.