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Updated: Jun 5, 2026

A Technical Guide for Performing Spectroscopic Measurements on Metal-Organic Frameworks
Published on: April 28, 2023
Quantification of ultra-trace molybdenum using 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid monosodium salt as a
Padmarajaiah Nagaraja1, Honnur Krishna, Anantharaman Shivakumar
1Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India. profpn58@yahoo.com
Abstract:
A simple, ultrasensitive, nonextractive spectrophotometric method has been developed for the assay of Mo(VI), which involves Mo-catalyzed oxidation of 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid monosodium salt (AHNDSA) by H(2)O(2) in acetic acid/sodium acetate buffer yielding an intense pink colored product with λ(max) of 540 nm. Beer's law is obeyed in the range of 10-240 ng/ml with molar absorptivity of 3.0137×10(5)L mol(-1)cm(-1). The LOD and LOQ were found to be 0.7696 and 2.565 ng/ml, respectively. The applicability of the method toward water and biological samples was tested and statistically compared with a reference method.

