Ninhydrin-sodium molybdate chromogenic analytical probe for the assay of amino acids and proteins.
A sensitive method has been proposed for the quantification of amino acids and proteins using ninhydrin and sodium molybdate as chromogenic substrates in citrate buffer of pH5.6. A weak molybdate-hydrindantin complex plays the role in the formation of Ruhemann's purple. The linear response for the amino acid, amino acid mixture and Bovine serum albumin is between 0.999 and 66.80μM, 1.52 and 38μM and 5 and 100μg/L, respectively. The molar absorptivity of the individual amino acid by the proposed reaction extends from 0.58×104to 2.86×104M-1cm-1. The linearity equations for the proposed ninhydrin-molybdate for amino acid mixture is Abs=0.021×Conc (μM)-0.002. The applicability of the proposed method has been justified in food and biological samples in conjunction with Kjeldahl method.
PG Department of Chemistry, St. Philomena's College, Bannimantap, Mysore 570015, India. Electronic address: shivakem77@yahoo.co.in.
Shivakumar
S
Anantharaman
DOS in Chemistry, Manasagangotri, Mysore 570 006, India.
Nagaraja
N
Padmarajaiah
Thamar University, Faculty of Applied Science, Department of Chemistry, Thamar, Yemen.
Naef Ghllab Saeed
NGS
Al-Tayar
Department of Pharmacy, Kathmandu University, Nepal.
Ashwinee Kumar
AK
Shrestha
D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D002417:Cattle; D006863:Hydrogen-Ion Concentration; D008982:Molybdenum / Q000737:chemistry*; D009555:Ninhydrin / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000032:analysis*
D000596:Amino Acids; D012710:Serum Albumin, Bovine; D008982:Molybdenum; C024687:sodium molybdate(VI); D009555:Ninhydrin
Amino acid; Hydrindantin; Kjeldahl nitrogen; Leucine equivalents; Ninhydrin; Ruhemann's purple; Sodium molybdate