A highly selective colorimetric sensor for cysteine in water solution and bovine serum albumin

A simple colorimetric sensor,2-bromonaphthalene-1,4-dione,has been developed for the cysteine detection. the sensor showed its best performance in a mixture of ethanol and hepes (5: 5,v/v) solution at ph of 7.0. the results of uv-vis and fluorescence indicated that 2-bromonaphthalene-1,4-dione was selective and sensitive for cysteine detection without the interference of other amino acids (cysteine,alanine,arginine,aspartinie,glutamine,glycine,histidine,isoleucine,leucine,lysine,methionine,proline,serine,threonine,phenylalanine,valine,tryptophan,and hydroxyproline). 2-bromonaphthalene-1,4-dione also showed binding ability for cysteine in bovine serum albumin and could be used as a potential colorimetric sensor among eighteen kinds of natural amino acids. importantly,the recognition of cysh could be observed by naked eye. © 2016 xuefang shang et al.