Synthesis of Ag-AgCl nanoparticles capped by calix[4]resorcinarene-mPEG conjugate and their antimicrobial activity

Abstract

© 2020 Elsevier B.V. The growing resistance of bacteria to traditional antibiotics makes it necessary to develop new antimicrobial agents with the dissimilar mode of action such as Ag and AgCl nanoparticles. Here the synthesis of silver NPs in the colloidal solutions of calix[4] resorcinarene-mPEG conjugate C11-mPEG was reported. NPs were synthesized under varied conditions: different Ag+/C11-mPEG molar ratio, presence/absence of reducing agent (NaBH4), in dark or LED light exposure. It was found that in all cases Ag-AgCl NPs, stabilized by C11-mPEG, were obtained with the difference in the Ag NPs content and sizes. Physicochemical characteristics of the Ag-AgCl@C11-mPEG NPs were evaluated by UV–vis, FT-IR, XRPD, XRF, DLS, and TEM methods. The antimicrobial activity of NPs against Gram-positive and Gram-negative bacteria and fungi was studied and the preferred antimicrobial activity against Gram-positive bacteria was found. The proposed scheme of Ag-AgCl@C11-mPEG NPs and the influence of NPs content on the antimicrobial activity were discussed.