68BIOANALYTICAL METHOD DEVELOPMENT AND REACTION RATE STUDY OF KAEMPFEROL IN ALBINO RATS PLASMA USING RP-HPLC METHODA rapid and specific bioanalytical method was developed for Kaempferol (100 mg) in albino rat plasma using ibuprofen as an internal standard (IS) and bioequivalence study has also been carried out in reaction rate monitoring of acetylation of 2-Thiohydantoin.The sample was prepared by liquid–liquid extraction with acetonitrile yielding almost near 100% recoveries of Kaempferol. Chromatographic separation was achieved with a Lichrocart C18 column (250mm x 4mm i.d. particle size 5μm) using Photo Diode Array detector using ibuprofen as an internal standard (IS). The mobile phase consisting of Potassium dihydrogen Phosphate buffer (0.05M, pH 2.1) and acetonitrile (65: 35 v/v) with 0.1% triethylamine at a flow rate 1.5mL/min. The detection was made at 370nm the retention time for Kaempferol is 8.07. The calibration curves were linear (r2 > 0.999) in the concentration range of 50-2.5ng ml−1. The extraction efficiency for the Kaempferol was more than 99.99%. The within and between day precisions in the measurement of four tested concentrations were in the range of 0.89–9.1% and 2.1–10.1% R.S.D., respectively. The developed procedure was applied to assess the pharmacokinetics of Kaempferol following administration of 50ng/kg oral dose of Kaempferol to healthy albino rats. The described method was established as a rapid analytical tool in a pharmacokinetic study requiring short retention time, high precision, sensitivity and small volumes of plasma for analysis of Benzo pyran derivatives.kishoreshore@gmail.comResearch322012Kaempferol,First order kinetics,RP-HPLC, PDA detector,BioequivalenceKishore Konam,Rakesh Chinta, Punuri Samuel Lukaraju,Mohan Gandhi Bonthu,Hari Prasad Pottabathula5 Department of Pharmaceutical Analysis and Quality Assurance, Sree Nagarjuna College of Pharmacy, Kadipikona, Warangal, Andhra Pradesh, India.,Department of Pharmacology, Azad College of Pharmacy, Moinabad, R.R. Dist, Andhra Pradesh, India.,Department of Pharmaceutical Chemistry, Bharat institute of Technology, Hyderabad, Andhra Pradesh, India.,Department of Pharmaceutical Analysis, K.G.R.L. College of Pharmacy, Bhimavaram, Andhra Pradesh, India,Department of Industrial Pharmacy, Swami Ramananda Tirtha Institute of Pharmaceutical Sciences, Nalgonda, Andhra Pradesh, India.