title: High performance liquid chromatographic determination of folic acid and its photodegradation products in the presence of riboflavin.
abstract: A high performance liquid chromatographic procedure was developed to determine folic acid and its photodegradation products, p-aminobenzoic acid, pterine-6-carboxylic acid, p-aminobenzoyl-L-glutamic acid, and pteroic acid in the presence of riboflavin. The method involves reversed phase, paired-ion chromatography on mu-BondaPak C18 column using a UV detector (254 nm), and isocratic solvent system (at ambient temperature) comprising 0.017 M monobasic potassium phosphate, tetrabutyl ammonium hydroxide solution (20%, aqueous) and methanol (870:15:250, v/v). The range of quantitation for the individual compounds was found to be: p-aminobenzoic acid, 0.01 - 1.25 x 10(-5) M; pterine-6-carboxylic acid, 0.01-2.0 x 10(-5) M; p-aminobenzoyl-L-glutamic acid, 0.02-2.0 x 10(-5) M; pteroic acid, 0.02-2.5 x 10(-5) M; folic acid, 1.0-5.0 x 10(-5) M; riboflavin, 1.0-5.0 x 10(-5) M. Linear regression analysis of the data demonstrates adequate performance of the method in terms of accuracy and precision (R. S. D. 3%). The method is specific, rapid and convenient and has been applied to photodegradation studies of folic acid in the presence and absence of riboflavin.
authors.affiliation: Department of Chemistry, University of Karachi, Pakistan.
authors.forename: M J
authors.initials: MJ
authors.lastname: Akhtar
authors.forename: M A
authors.initials: MA
authors.lastname: Khan
authors.forename: I
authors.initials: I
authors.lastname: Ahmad
mesh_terms: D010129:4-Aminobenzoic Acid / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005492:Folic Acid / Q000032:analysis* / Q000737:chemistry; D005971:Glutamates / Q000032:analysis; D016014:Linear Models; D010782:Photolysis; D011622:Pterins / Q000032:analysis; D012256:Riboflavin; D013056:Spectrophotometry, Ultraviolet
chemical_list: D005971:Glutamates; D011622:Pterins; C005584:pteroic acid; D005492:Folic Acid; C011398:4-aminobenzoylglutamic acid; D010129:4-Aminobenzoic Acid; D012256:Riboflavin