Title : In-vitro assessment of oil formulation & rat plasma stability of multiple pyrethroids using HPLC & LC-MS/MS based methods
Pyrethroids are the synthetic insecticides, widely used in household, agricultural field etc to kill pests and insects. Their extensive and unrestricted usage leads to human exposure to these toxic chemicals. These compounds are known to show toxicities like hepatotoxicity, cardiotoxicity, non-locomotor activities but preferentially neurotoxicity. Pyrethroids have short half life and rapidly get metabolized to different metabolites, raising a reason for its stabilization to detemine its true pharmacokinetic profile. Few scientists have done and reported stabilization of pyrethroids in rat plasma but none of them have reported a proper comparative study. In this study, we intend to stabilize pyrethroids in rat plasma using individual esterase inhibitors like sodium fluoride (NaF), thenoyltrifluoroacetone (TTFA), bis-nitrophenyl phosphate (BNPP), phenylmethanesulfonyl fluoride (PMSF), ethylenediamine tetra acetic acid (EDTA) and eserine to prevent non-specific metabolization of seven pyrethroids namely, bifenthrin, fenpropathrin, λ-cyhalothrin, cyfluthrin, cypermethrin, fluvalinate and deltamethrin in plasma matrix. This study can help us to identify the most potent carboxylesterase inhibitor and gives a simple and sensitive LC-MS/MS based method for the simultaneous determination of multiple pyrethroids. In present study, we have also developed an oil formulation of pyrethroids and have successfully performed its stability assessment for twenty days. Unlike other formulations, our formulation has shown stability upto ten days of its formulation. Thus, this formulation can be stored and used effectively for ten days.