Configuration-regulated highly luminescent hydrogen–organic frameworks for detection of phenelzine and propofol

Sensing and monitoring psychotropic and controlled substances in water are critical to health safety. Herein, two luminescent hydrogen–organic frameworks (HOFs), namely TPPA-BDC and TPPA-BTC, were synthesized using the same organic fluorophore (tris(4-(pyridin-4-yl)phenyl)amine, TPPA) with different fluorophore arrangements. Compared to TPPA-BTC, TPPA-BDC has stronger fluorescence emission, which is attributed to the smaller non-radiative energy loss, as indicated by density functional theory (DFT) calculations. Owing to the excellent luminescence of TPPA-BDC, it displays high sensitivity, great selectivity, and a low limit of detection toward phenelzine and propofol as well as a preeminent anti-interference ability for sensing targets in complicated environments. More importantly, the recognition mechanism of phenelzine is revealed via a rarely explored structural reorganization with a well-resolved structure. DFT calculations revealed that the synergistic effect realizes the “turn-off” responsive sensing of propofol, including both efficient photo-induced electron transfer process to propofol induced by TPPA-BDC and the dynamic quenching effect. This study provides a representative case of the fabrication of configuration-induced highly luminescent HOFs and opens the possibility for the application of HOF-based fluorescent probes in drug sensing.