Application of Spiking Technique Coupled with Derivative Spectrophotometry for the Analysis of a Novel Anti-diabetic Combination of Two Coformulated Drugs with Highly Different Concentrations

摘要

A new first derivative spectrophotometric method was developed for simultaneous determination of empagliflozin and metformin with successful application on their pharmaceutical preparation. A well-established spiking technique was used to increase the concentration of empagliflozin after extraction from tablets to eliminate the deviation from Beer’s law which occurs in case of low contribution. Scan of the zero order spectra of the studied drugs was carried out in the range from 200 to 300 nm using Spectra Manager II software® and then the amplitudes of the first derivative spectra were measured against methanol as blank at 223.5 nm and 233.5 nm for metformin and empagliflozin, respectively. Validation parameters were satisfactory over the concentration range of 2-12 μg/mL for both drugs using the proposed economic first derivative spectrophotometric method.