Estimation of the Folic Acid Using Zero Order, Area Under Curve and First Derivative Spectrophotometric Methods in Pure and Marketed Tablet Formulations

Abstract

Three simple, inexpensive and nontoxic spectrophotometric methods have been used for determination folic acid in pure and market formulation tablets. Linearity was founded in the range 620 mg.l -1 for the all three methods, the detection limits was found to be 0.261 for zero order method, 0.006 for AUC method and 3.800 for first derivative method. The RSD% was found to be less than 0.856 indicating a good accuracy and precision of three proposed methods. The results of zero order, AUC and first derivative methods were statistically compared with those obtained by the official standard method using the F-test and t-test and found to be a good agreement. [DOI: 10.22401/JNUS.20.3.07] Keyword: folic acid, zero order, AUC, first derivative, spectrophotometric. Introduction Folic acid(FA) as in fig.1 is an organic compound as a part of the vitamin B complex [1] , FA is formed by the some plants, microorganisms and FA can also be found in human and animals body like liver and bone morrow [2] . There are many methods are used for the estimation folic acid including; determination FA in fruits, vegetable, cereal and pharmaceuticals tables by HPLC method [3-7] , FTIR spectroscopy [8] , capillary electrophoresis (CE) [9] , spectrophotometric [10,11] , Gold nano partical [12] , chemiluminescence [13] voltammetric [14] and flow injection [15] . The aim of this study is developed a direct , sensitive and economic spectrophotometric method to estimation folic acid in pharmaceuticals tablets in Iraqi markets. Fig.(1): Foilc acid chemical structure. Material and Method Preparation of standard solutions 1. 0.05 gm of pure folic acid (M.Wt=441.404 gm.mol -1 ) was a gift from the state company for the drug industry Samara-Iraq (SDI), Folic acid was dissolved in 50 ml distilled water to obtain stock solution 1000 mg.l -1 , then was transferred 5 ml from stock solution to 50 ml volumetric flask and completed to the mark with distilled water to obtained concretions equal to 100 mg.l -1 . 2. Series of standard solution were prepared using different volumes (3, 5, 7, 9 and 10 ml) from 100 mg.l -1 solution and diluted to 50 ml with distilled water to obtained concretions of pure folic acid equal to (6, 10, 14, 18 and 20 mg.l -1 ). 3. Assay of market sample preparations: ten tablets of folic acid (5 mg, Actavis Barnstaple, Ex 328NS, US) were weighed and ground into a powder, the tablets powder 0.01 gm of folic acid market sample weighed and dissolved in distilled water and transferred to 100 ml volumetric flask to obtain concentration equal to 100 mg.l -1 ; then was transferred (6 and 10 ml) from folic acid market sample 100 mg.l -1 to 50 ml volumetric flask and