共聚物 P(NIPAM-co-AAEA) 的合成及其抗菌凝胶涂层的性能

Firstly, the copolymer poly[(N-isopropyl acrylamide)-co-(N-(2-hydroxyethyl)acrylamide)] (P(NIPAM-co-HEAA)) was obtained by reversible addition fragmentation chain transfer (RAFT) polymerization reaction at different feed ratio of NIPAM/HEAA. Then, the double bond functionalized copolymer poly[(N-isopropyl acrylamide)-co-(2acrylamidoethyl acrylate)] (P(NIPAM-co-AAEA)) was obtained by coupling with acryloyl chloride. Finally, thermo-sensitive hydrogel coating was fabricated by ‘one step’ photocrosslinking reaction of thermo-sensitive copolymer P(NIPAM-co-AAEA) and double bond functionalized antibacterial peptides (AMPs) on polydimethylsiloxane (PDMS). The thermo-sensitive copolymers were characterized by proton nuclear magnetic resonance (¹H-NMR) to identify the ratio of polymeric monomers. The AMPs were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Then, the modification of the hydrogel on the substrate and the morphology were characterized by fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM), respectively. The thermo-sensitivity of the hydrogel coatings were confirmed by static water contact angle (WCA) as a function of temperature variation. Finally, the antifouling and antibacterial properties of the hydrogel coating were validated by bacterial LIVE/DEAD viability assays characterized by Confocal Laser Scanning Microscope (CLSM) and colony counting assays. The results showed that when the feed ratio of NIPAM/HEAA was controlled at the optimized value of 87∶13, the LCST of P(NIPAM-co-AAEA) was determined as 36.6 ℃, which was close to human body temperature 37 ℃. It is expected that these copolymers would present a thermo responsiveness under body temperature. Meanwhile, the prepared thermo-sensitive hydrogel coating exhibited expeted antifouling property and antibacterial activity.