Abstract
Tannic acid (TA) is a natural polyphenolic known for its antioxidant, antibacterial and anti-carcinogenic properties were used in this investigation to prepare bulk hydrogel and microgels. The poly(Tannic acid) (p(TA)) hydrogels in bulk were synthesized by using trimethylolpropane triglycidyl ether (TMPGDE) as crosslinker, and microgels were prepared in water-in-oil micro emulsion. Furthermore, p(TA) materials were chemically modified using different modifying agents such as 3-chloro-2-hydroxypropyl ammonium chloride (CHPACl), thioglicolic acid (TGA), chlorosulfonic acid (CSA), glycidyl methacrylate (GMA). The chemical modification of p(TA) particles with (CHPACl) is given in Figure 1. The details of morphological and physicochemical characterization were done via SEM, TGA, FT-IR, DLS and zeta potential measurements. The bulk hydrogels of p(TA) as potential wound dressing materials were tested for in vitro degradability in physiological and chronic wound healing conditions (pH 7.4, 37.5 °C), or acidic/basic conditions. The antioxidant properties of bare and modified p(TA) based materials were also investigated by employing FC, ABTS and DPPH scavenging assays. As TA molecule is known for strong antimicrobial properties against various bacteria, fungi, yeasts, and viruses; we also tested the p(TA) based materials for their antimicrobial susceptibility against Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538, and Bacillus subtilis ATCC 6633, Pseudomonas aeruginosa ATCC 10145, and Candida albicans ATCC 10231. Furthermore, bulk and micron sized p(TA) hydrogels and their modified forms for potential drug delivery devices are tested by the release of TA itself from p(TA) materials at pH 7.4 and 37.5 °C. Furthermore, biocompatibility of TA and p(TA) materials for apoptotic and necrotic effects against L929 fibroblast cells and A549 cancerous cells were examined to further illustrate their biomedical applications.
