Synthesis of Silver-Alginate Nanocomposites Using CaCl2 Gelling Agent for Antibacterial Gel Application Endang Susilowati, Sulistyo Saputro, Lina Mahardiani, Nanik Dwi Nurhayati, Budi Hastuti, Wirawan Ciptonugroho, Muhammad Iqbal Juniardi
Department of Chemistry Education, Faculty of Teacher Training and Education, Universitas Sebelas Maret, Surakarta, Indonesia
Abstract
Silver nanoparticles are known to have a broad antibacterial spectrum, but their stability and potential toxicity need to be controlled through a biocompatible matrix system. Alginate as an anionic biopolymer has the ability to form gels through ionic cross-linking with CaCl₂-, thus potentially becoming a stable silver nanoparticle carrier matrix while improving the physical properties of the gel for topical applications. This research was conducted in 2 stages. The first stage, namely the synthesis of silver-alginate (Ag/Alg) nanocomposite colloids with the help of microwave irradiation, with AgNO3 as a precursor agent, alginate as a reducing agent and stabilizer, and NaOH as an accelerator. The second stage, namely the preparation of Ag/Alg nanocomposite gel preparations with CaCl2 cross-linking (Ag/Alg-CaCl2). The formation of silver nanoparticles was identified by a UV-Vis spectrophotometer based on the localized surface plasmon resonance (LSPR) phenomenon. Furthermore, the formed Ag/Alg-CaCl2 nanocomposite gel was subjected to organoleptic tests, spreadability, adhesiveness, viscosity, pH, functional groups, morphology and antibacterial activity tests against S.aureus and E.coli bacteria. The results showed that silver nanoparticles were identified by the appearance of LSPR absorption bands at 408.5-412.4 nm. The greater the concentration of AgNO3, the more silver nanoparticles were produced. The addition of CaCl2 increased the spreadability, adhesiveness, and viscosity of the Ag/Alg-CaCl2 nanocomposite gel preparation. The functional groups of the Ag/Alg-CaCl2 nanocomposite gel preparation in the FTIR spectrum were influenced by the electrostatic interaction between CaCl2 and Alginate. Alginate has a smooth and homogeneous morphological structure, while the Alg-CaCl2 and Ag/Alg-CaCl2 gel preparations showed a hollow morphological structure. The higher the concentration of AgNP, the higher the antibacterial activity of the Ag/Alg-CaCl2 nanocomposite gel.
Keywords: nanocomposite, Silver nanoparticles, Alginate, CaCl2, gel, AntibacterialPlease Just Try to Submit This Sample Abstract
