An easy and efficient fluorescent method for detecting aldehydes and its application in biotransformation.

Water-soluble aldehydes (acetaldehyde, propionaldehyde) and non-water-soluble aldehydes (butyraldehyde and phenylacetaldehyde) were easily detected by an efficient fluorescent method with 5-aminofluorescein as probe. Under optimal detection conditions, 5-aminofluorescein could selectively respond to aldehydes with high sensitivity in comparison with other carbonyl compounds like ketones and acids. Thus, the proposed method was used to monitor microbial oxidation and succeeded in trapping transiently-produced aldehydes during biotransformation of primary alcohols by Gluconobacter oxydans.