Self-healable and conductive metal-nanocomposite double-network hydrogels with bioactive properties

Abstract

Nanocomposite hydrogels are a class of materials that generally subsume hydrophilic polymers and nanofillers. It is required that nanocomposite hydrogels should have various properties such as self- healing, conductivity, toughness, bioactivity, facile processing ability, and so on for practical applications. But it is unrealistic to have all the above-mentioned properties in a single nanocomposite hydrogel still now. Here, a double network polymer hydrogel consisting of Poly (vinyl alcohol)-Poly (Sodium 4-styrene sulfonate)-Poly(2-aminoethylenemethacrylate) polymers i.e. PVA-P(NaSS)-P(AEMA) has been reported. The obtained double network hydrogels containing copper ions i.e. PVA-P(NaSS)-P(AEMA)@Cu2+ hydrogel and copper nano particles (CuNPs) containing hydrogels i.e. PVA-P(NaSS)-P(AEMA)@Cu hydrogel are found to exhibit self-healing, conducting, high mechanical, bioactive and wound healing properties. The formation of CuNPs, PVA-P(NaSS)-P(AEMA) hydrogel, PVA-P(NaSS)-P(AEMA)@Cu2+ hydrogel and PVA-P(NaSS)-P(AEMA)@Cu hydrogel were characterized by UV-vis spectrometer, Fourier Transform Infrared (FT-IR) spectrometer and Field Emission Scanning Electron Microscopy (FE-SEM). Energy-Dispersive X-ray Spectroscopy (EDS) was used for elemental analysis and their abundance in PVA-P(NaSS)-P(AEMA)@Cu hydrogel. For testing mechanical properties of all hydrogels, Universal Testing Machine (UTM) was used. Electrochemical Impedance Analysis (EIA) was done for the measurement of conductivity of PVA-P(NaSS)-P(AEMA) hydrogel, PVA-P(NaSS)-P(AEMA)@Cu2+ hydrogel and PVA-P(NaSS)-P(AEMA)@Cu hydrogel. The antibacterial susceptibility of fabricated PVA-P(NaSS)-P(AEMA)@Cu against Escherichia coli (E. coli) and Staphylococcus aureus were evaluated by disk diffusion/Kibry–Bauer method using Ciprofloxacin and Gentamicin as a standard in agar medium. The wound healing properties of PVA-P(NaSS)-P(AEMA)@Cu hydrogel was done on certain cutting wound skin of long evam male rat and checked their healing properties with time. The FT-IR analysis of PVA-P(NaSS)-P(AEMA) hydrogel, PVA-P(NaSS)-P(AEMA)@Cu2+ and PVA-P(NaSS)-P(AEMA)@Cu hydrogel was done, through drying all the hydrogels in oven at first and made them powder as much as possible. Since, CuNPs are readily oxidized that is why EIS and Kibry–Bauer method were done immediately after preparation of PVA-P(NaSS)-P(AEMA)@Cu hydrogel.