Hello Dear Subhrajyoti Rath,

Refer to your query, to make a stable nanoemulsion of essential oil/ plant extract, generally a combination of surfactants is preferably used. There have one non-ionic surfactant like Tween 20/80 and one ionic surfactant like salt of benzene sulphonate and their blend makes an appropriate HLB value for the development of thermostable emulsion.

Please check my work below;

Article Development of nanoemulsion formulation of mustard oil, its ...

Thank yo so much sir Aloke Purkait for your kind reply