Analytical Sciences

Abstract − Analytical Sciences, 36(9), 1031 (2020).

Square-wave Adsorptive Anodic Stripping Voltammetric Determination of Antidiabetic Drug Linagliptin in Pharmaceutical Formulations and Biological Fluids Using a Pencil Graphite Electrode
Ahmed. H. NAGGAR,*1,*2 Gamal. A. SALEH,*3 Mahmoud. A. OMAR,*4,*5 Ahmed. M. HAREDY,*5 and Sayed. M. DERAYEA*5
*1 Chemistry Department, College of Science and Arts, Jouf University, Al-Qurayyat, 75911, Kingdom of Saudi Arabia
*2 Chemistry Department, Faculty of Science, Al-Azhar University, Assiut, 71524, Egypt
*3 Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Assiut University, Assiut, Egypt
*4 Department of Pharmacognosy and Pharmaceutical Chemistry, College of Pharmacy, Taibah University, Medinah, Kingdom of Saudi Arabia
*5 Analytical Chemistry Department, Faculty of Pharmacy, Minia University, Minia, Egypt
A simple, sensitive, low-cost, quick and reliable square-wave anodic stripping voltammetric method is described for the determination of the antidiabetic drug Linagliptin (LNG) in pure form, tablets, and spiked human urine and plasma samples. Using a pencil graphite electrode (PGE), cyclic voltammetry (CV) was applied to study the electrochemical behavior of LNG. In a Teorell–Stenhagen buffer (pH 5.5) containing 0.1 M NaClO4 as a supporting electrolyte, the LNG yields an irreversible well-defined oxidation peak at about 1.2 V vs. Ag/AgCl electrode. The various affecting factors, such as the pH, buffer type, supporting electrolyte, accumulation potential, scan rate and accumulation time, were tested and optimized. Also, square-wave adsorptive anodic stripping voltammetric (SWAdASV) studies show that the peak current various linearly over the LNG concentration range of 0.24 – 5.20 μg mL−1 (R2 = 0.9994). The detection and quantification limits were calculated to be 0.10 and 0.33 μg mL−1, respectively. The proposed procedure exhibits a good precision, selectivity, and stability and was applied successfully to determine the LNG in pharmaceutical formulations (tablets) and biological fluids (spiked human urine and plasma samples).