Overdose of alkaloid drugs often causes significant damage to the human body. However, the researches about detecting alkaloids are rare and thus, it is urgent to develop a facile method to detect alkaloids. Here, four COFs TbAzo, HTbAzo, DHTbAzo and TpAzo with different ratios of β-ketoenamine/imine are synthesized When the ratio of β-ketoenamine/imine is 1/2, HTbAzo shows unique photoluminescence behavior, and the fluorescence emission is much higher than the other three COFs in water. HTbAzo shows different fluorescence responses to isoniazid (ratiometric) and colchicine (turn-off) with very low detection limits (12.60 μM for isoniazid and 1.03 nM for colchicine). HTbAzo was also applied in fluorescence sensing of isoniazid and colchicine in human serum, and the detection limits of isoniazid and colchicine were calculated to be 71.5 μM and 4.64 μM in the low concentration range, respectively. In addition, HTbAzo was also used to monitor pH (turn-on) in water with excellent linear relationship in the range of pH= 4.00–12.00 and a very low detection limit of 0.02. This work provides a new idea for improving the luminescence performance of COFs, and the different fluorescence responses of HTbAzo to alkaloids and pH make it a multifunctional sensor applied in real life.

过量服用生物碱类药物往往会对人体造成重大损害。然而，关于检测生物碱的研究很少，因此迫切需要开发一种简便的检测生物碱的方法。本文合成了四种不同β-酮烯胺/亚胺比例的COFs TbAzo、HTbAzo、DHTbAzo和TpAzo，当β-酮烯胺/亚胺比例为1/2时，HTbAzo表现出独特的光致发光行为，荧光发射远高于水中的其他三个COF。HTbAzo 对异烟肼（比例）和秋水仙碱（关闭）具有不同的荧光响应，检测限非常低（异烟肼为 12.60 μM，秋水仙碱为 1.03 nM）。HTbAzo还应用于人血清中异烟肼和秋水仙碱的荧光传感，计算出异烟肼和秋水仙碱的检出限分别为71.5 μM和4。在低浓度范围内分别为 64 μM。此外，HTbAzo 还用于监测水中的 pH（开启），在 pH=4.00–12.00 范围内具有出色的线性关系，检测限极低，仅为 0.02。该工作为提高COFs的发光性能提供了新思路，HTbAzo对生物碱和pH的不同荧光响应使其成为现实生活中应用的多功能传感器。