AMCA (7 - amino - 4 - methyl - 3 - coumarinacetic acid) is a blue fluorescent dye that is a non - sulfonated version of the Alexa Fluor® 350 dye. It is often used as a contrasting probe for double - and triple - labeling in immunofluorescence microscopy, arrays, and in situ hybridization. The desirable properties of AMCA dyes include a relatively large Stoke’s shift and resistance to photobleaching.
This reagent is supplied as Boc protected derivative to ensure compatibility with Fmoc solid phase peptide synthesis. The hydrophilic spacer arm contains a hydrophilic, 4-unit, polyethylene glycol (PEG) group imparts water solubility of the labeled peptide resulting in less aggregation when stored in aqueous solution. Spacers of different lengths are available upon request.