Highly sensitive and selective detection of tryptophan by antipyrine based fluorimetric sensor

For the detection of tryptophan (TP), organic molecule based on antipyrine (AP) has been synthesized. UV-vis and fluorimetric study has been used to confirm the sensing mechanism of AP with TP and theoretical explanations based on DFT calculations were also employed. The presence of numerous interfering biomolecules such alanine, asparagine, ascorbic acid, creatine, creatinine, cysteine, dopamine, glutamine, histidine, leucine, phenylalanine proline and urea could be optically distinguished by the AP by a change in colour from yellow to intense yellow fluorescence. The impressive sensing performance of AP sensor exhibits rapid response, remarkable sensitivity and selectivity towards TP with excellent limit of detection, high quantum yield and binding constant of 2 × 10⁻⁷ mol/L, 0.89 and 1.12 × 10⁶ M⁻¹ respectively.