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PubMed · 10708399

A validated quantitative colorimetric assay for gentamicin.

P Frutos·S Torrado·M E Perez-Lorenzo·G Frutos
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Abstract

A colorimetric procedure was developed for the quantification of gentamicin. The method was based on the ninhydrin reaction with primary and secondary amines present in the gentamicin. This reaction produces a purple colour. The effects of several factors including pH, ninhydrin concentration and reaction time were investigated to optimize the assay method. Using the assay protocol, the absorption of the gentamicin-ninhydrin mixtures at 400 nm had a linear relationship with the gentamicin concentration ranging from 30 to 120 microg/ml. The colorimetric gentamicin assay reported herein is of great practical value because it is reproducible, sensitive, simple and extremely inexpensive.

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ColorimetryGentamicinsHydrogen-Ion ConcentrationKineticsNinhydrinReproducibility of ResultsSensitivity and SpecificityJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

P Frutos, S Torrado, M E Perez-Lorenzo, G Frutos. 2000. A validated quantitative colorimetric assay for gentamicin.. https://doi.org/10.1016/s0731-7085(99)00192-2

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