Ecofriendly Ethyl Cellulose Microsponges of Citronella Oil: Preparation, Characterization and Evaluation of Cytotoxicity and Larvicidal assay

Abstract

Background: Citronella Oil (CO) was used by the Indian army as mosquito repellant to repel mosquitoes at the beginning of the 20th century and later in 1948, it was registered in the USA for commercial purposes. Due to its ecofriendly nature, CO possesses immense potential as a mosquito repellent. Methods: Citronella oil is a valuable alternative to synthetic mosquito repellents commonly used nowadays. However, its volatile nature, poor stability in air and high temperature restrict its application. Its direct application on skin may lead to skin irritation. To surmount the above-mentioned issues, the present research aims to develop Microsponge (MS), a novel dosage form for enhancing the utility and safety of CO. Quasi emulsion solvent diffusion method was chosen for crafting MS using ethyl cellulose with various drug-polymer ratios and characterized. In vitro cytotoxicity evaluation was also carried out to check the dermal safety of COMS. Results: The present results revealed that the size of all prepared formulation lies in the micro range (20 ± 3 to 41 ± 4 μm), with good payload (42.09± 3.24 to 67.08± 6.43%). The results of FE-SEM depicted that MS were spherical in shape with porous nature. Cytotoxicity results indicated that COMS were safe on skin cells, when compared to pure CO. The optimized MS were also assessed for larvicidal assay against larvae of Anopheles culicifacies. Conclusion: The CO micro-formulations were found to possess enhanced stability of this oil. Entrapment of CO in MS resulted in a better vehicle system in terms of safety, stability and handling benefits of this oil.