Rapid useful and easy spectrophotometric method for quantitative analysis of Gliclazide(GLZ)in raw material and tablets pharmaceutical formulation has been described. This method is based on the formation of yellow ion-pair complex between (GLZ) and Bromocresol purple (BCP) in Toluene medium. Different parameters affecting the reaction such as: effect of solvents, time, reagent concentration, correlation ratio, etc. were optimized. The absorbance of the formed complex GLZ-BCP was measured by visible spectrum at absorption maximum 415 nm. The range of linearity was(4.85 – 113.19) µg/mL,regression analysis had a good correlation coefficient R2 = 0.9999. The limit of detection (LOD)and limit of quantification (LOQ)were to be 0.47µg/mL and 1.44µg/mL respectively. The average percent recovery of (GLZ) was found to be (99.73 – 100.41)%. The method was successfully applied for the determination of (GLZ) in tablets pharmaceutical formulations in Syrian pharmaceutical products: UNICRON. The proposed method is simple, direct, and sensitiveand does not require any pre-extractionprocess. Thus, the method could be ready to apply in routine analysis and quality control.

Simple and rapid spectrophotometric method was developed and applied to determine Glibenclamide (GB) by zero spectrophotometric method and first derivative spectrophotometric method for determining of (GB) in the presence of Metformin hydrochloride (MET). Zero spectrophotometric (ZS) method was applied for the determination of (GB) at λmax = 300 nm. Linearity range was (4 – 360) μg/mL. Regression analysis showed a good correlation coefficients R2 = 0.99993. The limit of detection (LOD) and limit of quantification (LOQ) were to be 0.65 μg/mL and 2.31 μg/mL, respectively.  First derivative spectrophotometric (1DS) method was applied for the determination of (GB) in the presence (MET). (GB) was determined at 317 nm (1D317). Linearity ranges were (4 – 240) μg/mL for (GB). Regression analysis showed a good correlation coefficients R2 = 0.999914. The limit of detection (LOD) and limit of quantification (LOQ) were to be 0.60 μg/mL and 1.83 μg/mL for (GB). The proposed zero spectrophotometry method was applied to analysis individual (GB), and the derivative (1D317) method was applied to analysis (GB) individually or combined with (MET) in Syrian trademark drugs. The proposed method is simple, direct, sensitive and do not require any extraction process. Thus, this method could be readily applicable for the quality control and routine analysis.