Abstract
A new simple, cheap, and rapid method to increase the sensitivity of pencil graphite electrode (PGE) to determine Linagliptin (LNG) was developed by modified PGE with copper microparticles (Cu-PGE). The preparation of the disposable modified sensor electrode depended on the electrodeposition of Cu-microparticles on the GPE that can be applied for determined LNG by complexed it with Cu+2 ions and measure the LNG-Cu complex onto the Cu-PGE improved. The preparation of this modified electrode is easy, simple, and cheap and has high sensitivity. The modified electrode detected the LNG in the LNG-Cu complex in the range from 47.25 - 283.53 ng mL(-1) with detection and quantitative limits of 6.23 and 20.77 ng mL(-1), respectively, with correlation coefficient 0.9995. The proposed method was applied with success to determined LNG in the dosage form, spiked urine, and spiked plasma samples; additionally, the obtained modified electrode was put in comparison with the reported electrodes.