The effect of syrup simplex concentration on the physicochemical stability of Gembili’s inulin (Dioscorea esculenta (Lour.) Burkill) nanosilver colloid

Abstract

Gembili (Dioscorea esculenta) tuber's inulin is a successful bioreductor agent that forms a nanosilver with a size of 481.4 nm and is stable for 30 days at 4 C storage. That nanosilver has immunomodulatory activity and is proven safe from the results of acute toxicity tests at a dose of 4 mg/kgBW. However, a drug delivery system is needed to be developed as a supplement product. The syrup was chosen because alcohol free, has a better taste, measured dose, and stable to maintain of the active substance compared to elixir, solution, and suspension. Syrup simplex as a syrup base affects stability because it has the potential to form crystals during storage. This research aims to determine the effect of syrup simplex concentration on the physicochemical stability of nanosilver colloid. The research was conducted with the biosynthesis process using gembili's inulin, nanosilver characteristic, modified syrup formula, and stability test. Nanosilver syrup was prepared by modifying the syrup simplex concentration of 20%, 40%, and 60%. Optimum dose of nanosilver as imunomodulator was added, then tested the physicochemical; stability, including organoleptic, pH, and viscosity, before and after storage with temperature variations of 4 °C and 40 °C for six cycles. The choosen formula then analysis using FT-IR and sugar reduction content. Data analysis using SPSS 21.0 Windows with Oneway ANOVA. The results showed that the concentration of syrup simplex affected consistency, pH, and viscosity. The syrup simplex concentration of 60% met the requirement with a medium thick consistency, pH 5.25±0.03, a viscosity of 92±2.6 cps, reducing sugar content was 20.59% ±0.002, and the FTIR profile showed that it still contained nanosilver which was indicated by the presence of Ag-N groups compared to silver nitrate solution.