Using Multivariate Calibration Method (Inverse Least Squares) for the Simultaneous Spectrophotometric Determination of Sulfadiazine and Trimethoprim in Dairy Products

Trimethoprim is a broad-spectrum bacteriostatic antibiotics to treat infections especially consumption urinary tract infections. In contrast sulfadiazine is used the treatment of bacterial infectious diseases, such as urinary tract infections, ear infections. The combination of sulphadiazine and trimethoprim has antibacterial effect against many gram positive and gram negative bacteria.In this method (inverse least squares) 81 binary mixtures were prepared in different levels in the range of 0.5 to 90 micromolar (mM). and the spectra of The RMSE values were 3.79 and 1.71 for sulfadiazine and trimethoprim respectively. samples recorded in the range of 210 to 340 nm for calibration and prediction series. The detection limits for Sulfadiazine and Trimethoprim calculated as 0.25 and 0.91 µmol.L- Respectively.This work Havegoodrepeatability with the relative standard deviations 1.34 % to5.68 % and 2.15 % to 4.95 % for sulfadiazineandtrimethoprim respectively. Finally, this method was successfully applied for simultaneous determination of trimethoprim and sulfadiazine in dairy products (low-fat milk and full-fat milk)