Antimicrobial and antioxidant properties of novel synthesized nanocomposites based on polystyrene packaging material waste

Investigation of chitin grafting: thermal, antioxidant and antitumor properties

In this study, firstly chitin was reacted with chloracetyl chloride to synthesize the macroinitiator chitinchloroacetate (Ch.ClAc). Then, graft copolymers of methacrylamide (MAM), diacetone acrylamide (DAAM), N-(4-nitrophenyl)acrylamide (NPA), and 2-hydroxyethyl methacrylate (HEMA) monomers were synthesized by atom transfer radical polymerization (ATRP). All of the polymers were characterized by FTIR spectra and elemental analysis. According to the elemental analysis results, the mole percent (y) of the macro initiator was found to be 17.39%. The thermal stability of all the polymers (chitin, Ch.ClAc and its graft copolymers) was determined by thermogravimetric analysis (TGA) method and the highest thermal stability was observed in the ungrafted raw chitin. DPPH• scavenging activity and antitumor activity of all polymers were then investigated. Ch.ClAc was found to be the polymer that inhibited the proliferation of tumor cells more than chitin and graft copolymers. It was observed that the antitumor (L1210 cell lines) effect increased with increasing time and concentration in all polymers.

Gamma irradiation green synthesis of (polyacrylamide/chitosan/silver nanoparticles) hydrogel nanocomposites and their using as antifungal against Candida albicans and anti-cancer modulator

Silver nanoparticles-loaded hydrogel nanocomposites are exploited for medicinal and pharmaceutical applications. Hydrogel nanocomposites were prepared from acrylamide (Am), chitosan (CS) and AgNO3 utilizing gamma rays. Diverse variables were applied in preparation of silver nanoparticles-laoded hydrogel nanocomposites of (PAm/CS)-AgNPs such as influence of radiation dose and influnece of CS concentration. Diverse techniques were utilized to characterize hydrogel nanocomposites; Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), Transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and scanning electron microscopy (SEM). Results confirmed formation of silver nanoparticles-loaded hydrogel nanocomposites of (PAm/CS)-AgNPs. Antifungal activity of (PAm/CS)-AgNPs hydrogel nanocomposites on viability of C. albicans was esitmated. Results displayed the efficient microbial inhibition activity of treatment against C. albicans compared to control. Furthermore, (PAm/CS)-AgNPs hydrogel nanocomposite against cervical cancer HeLa cell line was investigated. Cytotoxicity of (PAm/CS)-AgNPs hydrogel nanocomposites on prior cancer cell line empolyed to prohibition of cell growth assesssed by MTT test. HeLa cancer cell is treated by (PAm/CS)-AgNPs for 48 h exposed a potential apoptotic activity by noticeable up-regulation of p53 gene expression. Moreover, anticancer activity was investigated by down-regulation of platelet-based growth variable receptor beta (PDGFR-β), Bcl2, Cathepsine, and MMP-2 gene expression. antioxidant activity was investigated and results showed antioxidant activity of (PAm/CS) hydrogel and (PAm/CS)-AgNPs hydrogel nanocomposite are 87.8% and 62.9%, respectively.