Cysteine and homocysteine chemosensor based on photochromic diarylethene with fluorine

A new photochromic diarylethene with formyl and fluorene groups, 1-[2-methyl-5-(9,9-diethyl-fluoren-2-yl)-3-thienyl]-2-[(2-methyl-5-formyl)-3-thienyl]perfluorocyclopentene, has been synthesized and characterized with single-crystal X-ray diffraction. Due to the interaction between the formyl group in its ring-closed isomer with cysteine/homocysteine, there was an evident color change in its absorption spectrum from blue to pale yellow and light brick-red upon addition of cysteine and homocysteine, respectively. Moreover, it was revealed that no obvious interference was observed during the titrations with the mixtures of cysteine/homocysteine and other amino acids. These results indicated that the diarylethene could be used as a colorimetric sensor to recognize cysteine/homocysteine with high selectivity.

A highly selective colorimetric chemosensor for cysteine and homocysteine was constructed based on a new diarylethene with formyl and fluorene groups.161