LAUSR

Tiagabine hydrochloride (TGB) is a clinically frequently-used drug for anti-convulsion and reducing epileptic frequency. Over administration of TGB could bring about adverse effects, such as speech disorder, depression and even suicidal tendencies. Therefore, accessible and sensitive assay for analysis of TGB becomes an urgent front-burner towards guiding clinical medication. Here, we present the first report on fluorescence turn-on detection of TGB in urine testing. In this protocol, a fluorescent dye, perylene tetracarboxylic acid imide derivative (PTAI), is found specifically occupies the sudlow site II of human serum albumin (HSA) and displays a new phenomenon of binding-induced quenching (BIQ). In presence of TGB, competitive binding of the TGB to the site II of HSA will trigger release of PDI, thus successfully light up the fluorescence of PTAI. This label-free assay enjoys broader working range (1-350 μM), lower detection limit (0.218 μM) than traditional liquid chromatography method and is uninterfered by the miscellaneous in the artificial urine. The BIQ probe highlights the merits of HSA as a quencher and a molecular recognition unit, open up a way for studying drug-HSA interaction mechanism and noninvasive pharmaceutical testing.