Synthesis of an Amine Moiety-Based Fluorescent Probe and the Relationship Between the Amino Substitution Position and Formaldehyde Detection Performance

A novel amine moiety-based fluorescent probe (BA) was prepared using diphenylacetylene as fluorophore and amino group as acceptor. The probe achieves detection of formaldehyde through fluorescence enhancement by inhibition the photoinduced electron transfer (PET) between diphenylacetylene and amino group. And the different formaldehyde detection performance of 2-(phenylethynyl)aniline (BA-1), 3-(phenylethynyl)aniline (BA-2) and 4-(phenylethynyl)aniline (BA-3) indicates that the position of amino recognition group on the benzene ring of diphenylacetylene has a significant impact on the detection ability of this type fluorescent probe. When the amino group is in the ortho-position of the benzene ring, probe BA-1 can rapidly enhance the fluorescence intensity within 20 min with limit of detection as low as 0.75 mu M; When the amino group is located in meta-position of benzene ring, the solution of BA-2 also exhibited a certain degree of fluorescence enhancement, but it is weaker than BA-1; When the amino group is at the para-position of benzene ring, BA-3 has almost no response to formaldehyde. Amine moiety-based fluorescence probes 2-(phenylethynyl)aniline (BA-1), 3-(phenylethynyl)aniline (BA-2), and 4-(phenylethynyl)aniline (BA-3) were synthesized from coupling reaction with diphenylacetylene as fluorophore and amino group as acceptor. The different formaldehyde detection performance of BA-1, BA-2 and BA-3 revealed that the position of amino group on the benzene ring of diphenylacetylene had a significant impact on the recognition for formaldehyde. image