309BIOANALYTICAL METHOD DEVELOPMENT & VALIDATION OF FULVESTRANT IN RAT PLASMA BY USING LIQUID CHROMATOGRAPHY AND TANDEM MASS SPECTROMETRY AS PER USFDA GUIDELINESA rapid, specific and sensitive high-performance liquid chromatography and electro spray tandem mass spectrometry (LC-MS/MS) method was developed and validated for estimation of Fulvestrant in Rat plasma using liquid-liquid extraction. The separation and quantification of Fulvestrant were achieved by reverse-phase chromatography on a YMC Pack ODS- AM column (150mm x 4.6mm x 5µm) with isocratic elution at a flow rate of 1mL/min using mobile phase consisting of 2mM Ammonium acetate in water and Methanol(10:90). Fulvestrant-D3 was used as internal standard. A heated electro spray ionization interface in negative polarity mode was used. The volume of plasma about 100 µl was used. The method was validated over the concentration range of 0.322- 35.823ng/ml. The within-batch and between-batch accuracy and precision were found to be within acceptance criteria at all QC levels. The recovery was found to be 85.94% and 96.67% for Fulvestrant and Fulvestrant-D3 respectively. The matrix effect from rat plasma was found to be within the acceptance criteria at all QC levels. The chromatographic run time was 5 min. smuthupharma81@gmail.comResearch4112013Fulvestrant,Liquid-Liquid Extraction,LC-MS/MS,Fulvestrant-D3Muthukumar S,Nagaraju G,David Banji, Sridhar Veeraraghavan,Satheesh Manikandan R S Thappali, Sandhya ChennupatiDepartment of Pharmaceutical Analysis & Quality Assurance, Nalanda College of Pharmacy, Charlapally, Nalgonda, Andhra Pradesh, India- 508001.,Department of Pharmaceutical Analysis & Quality Assurance, Nalanda College of Pharmacy, Charlapally, Nalgonda, Andhra Pradesh, India- 508001.,Department of Pharmaceutical Analysis & Quality Assurance, Nalanda College of Pharmacy, Charlapally, Nalgonda, Andhra Pradesh, India- 508001.,Incozen Therapeutics Pvt. Ltd, Alexandria Knowledge Park, Shameerpet, Hyderabad-50078, India,Incozen Therapeutics Pvt. Ltd, Alexandria Knowledge Park, Shameerpet, Hyderabad-50078, India,Incozen Therapeutics Pvt. Ltd, Alexandria Knowledge Park, Shameerpet, Hyderabad-50078, India