title: Colorimetric determination of macrolide antibiotics using ferric ion.
abstract: Macrolide antibiotics such as erythromycin, oleandomycin, spiromycin, and tylosin are found to react with Fe(3+) in the presence of an acetic acid-sulfuric acid mixture to form a colored product having a useful absorption band at 592 nm. Troleandomycin forms only a weakly colored product upon reaction. The molar absorptivity is about 2900 1 mol(-1) cm(-1) for erythromycin and the detection limit is 5 mug ml(-1). This colorimetric method permits the analysis of fermentation broths containing either erythromycin or tylosin without a separation step.
authors.affiliation: Department of Chemistry, Miami University, Oxford, OH 45056, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Gallagher
authors.forename: N D
authors.initials: ND
authors.lastname: Danielson