Application of Drug–Metal Ion Interaction Principle in Potentiometric and Conductometric Determination of Folic Acid

This study includes carefully selecting nine metal ions; magnesium, calcium, cobalt, nickel, copper, lead, chromium, iron and thorium to clarify their interaction with folic acid (FA) by potentiometric technique. The association constant of folic acid and the strength constants of the complexes made at ionic strength, I = 0.1molar NaClO4 in aquatic medium at room temperature were calculated. Complexes were obtained with metal - FA ratios of 1:1, 1:2 and/or 1:3 according to the nature of the metallic ions and folic acid. Also, the instruction of strength constants of the double complexed was tested. The connection of the complexes was determined through conductivity measurement method. The ionic balances of the FA and its complexes with diverse metallic elements in medium were examined. Simple, accurate, quick and little -cost potentiometric and conductivity procedures are used to determine folic acid (FA) in pure pharmaceutical samples. The potentiometric technique is built on the direct titration of folic acid in aqueous medium 0.1 M NaOH at µ=0.5NaClO4 and 25±1.0oС in the presence of a composite glass electrode and using the standard addition method, the detection and quantitation restrictions were establishing to be 0.005 milligram/ml, with a standard deviation, SD=0.002, and a correlation coefficient, R=0.9943 (n=5), and the linear concentration ranges were 0.005 to 0.07 mg/ml. This method was likewise used for the estimation of FA in pure solutions and tablets and satisfactory results were obtained. No interventions were detected in the occurrence of public constituents of the samples under study. The recovery of folic acid from different dosage tablets ranged from 97.3 to 98.6%.