Formulation and evaluation of bio-mosquito repellent air freshener gel from oil extract of cymbopogon citratus (DC.) Stapf (lemon grass) plant.

Synthetic based mosquito repellents pose varying degrees of threats to public health in most developing nations.  The developments has necessitated the need for environmentally friendly alternatives, which will have non-toxic, and biodegradable attributes. In this work, a mosquito repellent gel formulation was prepared from the essential oils of Cymbopogon citratus (DC.) Stapf (lemon grass) extracted using a steam distillation system. The yields of the extracted oils were determined and calculated under varying conditions. The oil extract was then purified in the micro column parked with silica gel and characterized using Gas Chromatography-Mass Spectrometry (GC-MS). The GC-MS analysis of the essential oil revealed the presence of β-pinene, isoneral, nerolidol and squalene chemical constituents. The optimized gels were evaluated for their appearance, pH, spreadability, macroscopic stability test, swelling index, and hedonic evaluation. The mosquito repellent potential was simultaneously compared with the positive control ‘Odomos’, a commercial gel sold in the open market within Jos, Plateau State, Nigeria by varying the repellency time. The outcome of the evaluations confirmed that the formulated gels were stable with normal skin pH. The hedonic test indicated that formulation F5 is the most potent gel with a C. citratus oil concentration of 5% in the formulation. This gel formulation promises to be an environmentally sustainable alternative for repelling mosquitoes.