Sutrisno Sutrisno, Husni Wahyu Wijaya, Siti Marfu’ah, Suharti Suharti, Jalifah Latif
Zn-oleate and Al-oleate are fatty acid metal salts known as synthetic metal soaps. These substances are not surface-active agents and therefore cannot function as cleaning agents. Concerning their structure, it can be thought to absorbed UV radiation and potentially use as a chemical sunscreen. Our study focused on synthesize metal (zinc and aluminum) oleate and sunscreen activity assay. The metal oleate synthesis was carried out using the trans-esterification method from the as-synthesized sodium oleate. Physicochemical properties of the as-synthesized zinc oleate and aluminum oleate were characterized using XRF, FT-IR, XRD, and SPF-based sunscreen activity assay by UV-spectrophotometry. The as-synthesized metal oleate resulted in the distinguishing feature. The as-synthesized zinc oleate is a white solid powder, melting point 64-71 °C, soluble in benzene, varnish oil, chloroform, and methanol, but un-soluble in water, ethanol, octanol, and petroleum ether. The as-synthesized aluminum oleate decomposed at 120 °C then its solubility properties are similar the as-synthesized zinc oleate. Zinc oleate is active as sunscreen (SPF 2.78), while aluminum oleate is inactive as sunscreen (SPF 0.96). © 2023 American Institute of Physics Inc.. All rights reserved.
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang No.5, Malang, 65145, Indonesia; Department of Chemical Sciences, Universiti Kebangsaan Malaysia, Selangor, Bangi, 43600, Malaysia
