Selective one-pot fluorescent probing technique for determination of tolterodine in dosage forms, content uniformity, and human plasma via coumarin synthesis.

Tolterodine tartrate (TTD), the inaugural antimuscarinic drug specifically created to treat overactive bladder syndrome, received FDA approval in 1998. Due to its widespread use in the local population since its approval, there is an urgent demand for the development of a spectrofluorometric method that is cost-effective, highly sensitive, selective, and reproducible. The spectrofluorometric method was developed by derivatization of TTD's phenol via Von Pechmann condensation. TTD reacts with ethyl acetoacetate (EAA) to form a highly fluorescent coumarin compound (Von Pechmann reaction) detectable at λem = 420 nm after λex = 359 nm. The TTD concentration and the fluorescence intensity were found to have linear relationship (r = 0.9996) between 100.0 and 1500.0 ng mL-1. This technique was successfully used for measuring TTD in its pure form, in the presence of co-formulated drug Tamsulosin Hydrochloride (TAM), and to assess pharmaceutical tablets for content uniformity. Furthermore, it was used to evaluate TTD concentrations in spiked human plasma samples. Additionally, environmental assessments using eco-scale, AGREE, and GAPI tools confirmed the method's eco-friendliness. This validated technique offers an efficient alternative for TTD analysis in pharmaceutical and biological matrices.