Abstract: Stabilized and transparent ZnO sol was prepared with zinc acetate dihydrate (ZAD) and potassium hydroxide (KOH) as starting materials and polyvinyl pyrrolidone (PVP) as surface modifying agent.The product was characterized and tested by X-ray diffraction,scanning electron microscopy,UV-visible absorption spectroscopy,fluorescence spectroscopy and high performance liquid chromatography.The influences of ZAD,KOH and PVP dosage on ZnO particle size and sol stability were examined.The minimum inhibitory concentration (MIC) value of ZnO sol were determined by agar dilution method with Staphylococcus aureus,Escherichia coli,Agrobacterium tumefaciens,Pseudomonas cepacia,Candida albicans and Aspergillus niger as testing objects.The photocatalytic activity of ZnO sol on degradation of methylene blue (MB),dimethoate and acephate solution was carried out.Results show that the ZnO sol product prepared with the stoichiometric composition of 10 mmol of ZAD,15 mmol of KOH and 1.6 g of PVP displays stable and uniformly distributed ZnO nanoparticle size.The growth of bacteria is inhibited effectively by the ZnO sol product,which has the best antibacterial effect on Staphylococcus aureus and Pseudomonas cepacia.Meanwhile,the ZnO sol product displays good photocatalytic activity on degradation of MB,dimethoate and acephate solution.

Key words: cosmetic additive, ZnO sol, sol method, bacteriostasis, photocatalytic activity