A novel L-tryptophan (L-Trp) fluorescent sensor (BTAP5) based on a functionalized pillar[5]arene has been developed. The sensor BTAP5 exhibits high selectivity and sensitivity (2.83 × 10−7 M) towards L-Trp in H2O/DMSO (7 : 3, v/v) solution. The recognition mechanism was studied by 1H NMR, electrospray ionization mass spectrometry and 2D NOESY.
![Graphical abstract: A novel functionalized pillar[5]arene-based selective amino acid sensor for l-tryptophan](http://hg.y866.cn/compound/lib/scimg/usr/1/C6QO00569A.jpg)
