A pillararene-based indicator displacement assay for the fluorescence detection of vitamin B1

The host-guest complex of the anionic macrocycle, carboxylato-pillar[6]arene (WP6) and the cationic dye, oxazine 1 (OX), functions as a fluorescent turn-on indicator displacement assay (IDA) for the cationic biomolecule, vitamin B1 (thiamine). The performance of the assay was demonstrated by applying it in the analysis of a poly B vitamin supplement. The structures of the OX-WP6 and B1-WP6 complexes were characterized by 1H NMR spectroscopy and theoretical calculations. To our knowledge, this is the first report on the construction of an IDA-based fluorescent sensor for vitamin B1.