Utilization of 4-Chloro-7-Nittobenzo-2-Oxa-1, 3-Diazol (NBD-CL) as Chromogenic Reagent for Determination of Metformin hydrochloride (MET) in Pharmaceutical Formulation


  • Abdalla Ahmed Elbashir University of Khartoum, Faculty of science, Department of Chemistry, Khartoum , Sudan
  • Omnia mohamed Abdallah alfaki University of Khartoum, Faculty of science, Department of Chemistry, Khartoum , Sudan




Spectrophotometric, Metformin, 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) pharmaceutical formulation


A new, simple, selective, precise and accurate spectrophotometric method for the determination of metformin in pharmaceutical formulation was developed and validated. The method was based on the reaction between metformin and 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) at alkaline medium (pH 12.0) to form brown adduct.  Beer’s law was obeyed in the concentration range of 20-100 μg mL-1  of  metformin at maximum wave length 465 nm . Under the optimized reaction conditions, the linear regression equation of the calibration curve was found to be y=0.003x +0.156 with a linear correlation coefficient (r=0.999). The limit of detection (LOD) and limit of quantification (LOQ) were found to be 5.8, 17.5 μg mL-1 respectively. The method is useful for routine analysis of metformin in quality control laboratories.


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Author Biographies

Abdalla Ahmed Elbashir, University of Khartoum, Faculty of science, Department of Chemistry, Khartoum , Sudan

University of Khartoum, Faculty of science, Department of Chemistry, Khartoum , Sudan

Omnia mohamed Abdallah alfaki, University of Khartoum, Faculty of science, Department of Chemistry, Khartoum , Sudan

University of Khartoum, Faculty of science, Department of Chemistry, Khartoum , Sudan


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How to Cite

Elbashir, A. A., & Abdallah alfaki, O. mohamed. (2019). Utilization of 4-Chloro-7-Nittobenzo-2-Oxa-1, 3-Diazol (NBD-CL) as Chromogenic Reagent for Determination of Metformin hydrochloride (MET) in Pharmaceutical Formulation. Asian Journal of Pharmaceutical Research and Development, 7(1), 19–23. https://doi.org/10.22270/ajprd.v7i1.455