Application and Equivalence Assessment for Determining Ethamsylate by Using Potassium Ferricyanide as Spectroscopic Probe Reagent

Abstract

In this paper, a novel method has been established to determine ethamsylate using potassium ferricyanide as a spectroscopic probe reagent. It has been demonstrated that Fe(III) is reduced to Fe(II) by ethamsylate, and that the formed Fe(II) reacts with potassium ferricyanide to form soluble prussian blue (KFe^III[Fe^II(CN)₆]). Beer’s law is obeyed in the range of 0.16 – 24.00 μg mL⁻¹ with the molar absorption coefficient of 2.1 × 10⁴ L mol⁻¹ cm⁻¹. The detection limit (3 σ/k) is 0.11 μg mL⁻¹. This method has been successfully applied to determine ethamsylate in pharmaceutical and serum samples with satisfactory results, and presented quite satisfactory credibility during method equivalence assessment.