Abstract:

We aimed to prepare a mosquito repellent gel with suitable consistency, refreshing skin feeling, safe and convenient use and long effective mosquito repellent time. In this paper, the effects of the mixture of different solubilizers, the dosage of different thickeners and the types and dosage of repellent on mosquito repellent gel were studied. The stability, appearance and skin sensation of mosquito repellent gel were evaluated by the combination of physical and chemical indexes such as cold and heat resistance and sensation, so as to determine the better basic formula. The mosquito repellent efficacy and safety of the better basic formula were evaluated. Then, in order to meet the needs of different target users, plant extracts with antibacterial and antioxidant activities were added to the basic gel formulation, and its effect on gel stability was observed. The results show that the gel prepared by the combination of 30% PEG400 and 15% propylene glycol can not only effectively increase the solubility of the repellent in water, but also has good stability and refreshing skin feeling. 0.8% carbomer 940 is used as the thickening agent of the mosquito repellent gel, which has good thickening performance and can achieve ideal skin feeling. The effective mosquito repellent time of DEET, BAAPE and Ecaritin repellent gel with 7.5% repellent addition is 6.8, 8.0 and 9.3 h, respectively, and the effect of the three self-made mosquito repellent gels is better than that of the mosquito repellent toilet water containing 12.5% mosquito repellent ester on the market. The animal skin irritation and eye irritation experiments show that the prepared mosquito repellent gel has no obvious irritation to the skin, but has slight irritation to the eyes. When the plant extract with antibacterial and antioxidant efficacy is added to the basic formula of the mosquito repellent gel, the transparency of the mosquito repellent gel decreases, especially with mosquito repellent ester as repellent. The physical and chemical properties of the mosquito repellent gel were tested, and the results show that all the indexes of the mosquito repellent gel meet the relevant requirements. The performance is relatively stable, and it is expected to have a good application prospect.

Key words: mosquito repellent gel, repellent, evaluation of mosquito repellent efficacy, stability, safety