SURFACE CLICK REACTION BETWEEN ACETYLENE-DECORATED POLYMERIC PLATFORM AND AZIDE-DECORATED COMPOUNDS

A proof on concept study was conducted in the quest for dual-functional surfaces that provide both biopassivity and bioactivity. It presents the development of a biopassive platform that readily binds to bioactive molecules via copper-catalyzed acetylene-azide cycloaddition reaction. Acetylene-decorated poly(2-methyl-2-oxazoline) (PMOXA) brushes were grafted on an Nb2O5 surface. This biopassive brush platform was then exposed to various azide-decorated compounds of different sizes (molecular weight) and chemical structure, i.e. benzyl, mannose, and antimicrobial peptide (AMP), to react through the cycloaddition reaction. The different nature of the compounds clicked to the brushes requires different strategies of characterization. Time of flight-secondary ion mass spectroscopy (ToF-SIMS) results showed that benzyl-triazole-characteristic fragments were successfully bound to the surface. Fluorescence spectroscopy results indicated that mannose-azide molecules tagged with dye-carrying Concanavalin A (Con-A) could bind to the PMOXA-acetylene brush via specific and, to some extent, nonspecific interactions. Similarly, optical waveguide light-mode spectroscopy (OWLS) and quartz crystal microbalance-dissipation (QCM-D) analysis showed a successful reaction between AMP-azide and the PMOXA-acetylene brush platform. Together, these results validated the original approach of generating dual-functional surfaces using a click reaction between oxazoline brushes and a variety of ligands relevant to a range of applications.

Automated summary

A proof of concept study was conducted to develop dual-functional surfaces that can provide both biopassivity and bioactivity. A biopassive platform was created by grafting acetylene-decorated PMOXA brushes onto an Nb2O5 surface. Various azide-decorated compounds of different sizes and chemical structures were then reacted with the biopassive brush platform through a click reaction. The characterization results showed successful binding of benzyl-triazole fragments, specific and nonspecific interactions between mannose-azide molecules and the PMOXA-acetylene brush, and a successful reaction between AMP-azide and the PMOXA-acetylene brush platform. These results validated the original approach of generating dual-functional surfaces.