通过单个荧光传感器同时检测多种分析物非常有吸引力。在这项研究中,研制了磷掺杂石墨氮化碳量子点(P-CNQDs),通过三种不同的响应机制实现多模式感知。该制备涉及使用三聚氰胺作为碳和氮源以及磷酸二氢铵作为磷源。通过化学氧化和水热法成功合成了均匀和窄分布的P-CNQDs,平均尺寸为2.4nm。这些独特的P-CNQD通过响应于Ag+的光诱导电子转移(PET)表现出荧光猝灭。此外,氢键的形成以及P-CNQDs-Ag和环丙沙星(CIP)之间的配位相互作用通过螯合增强荧光(CHEF)机制导致对CIP的明显荧光响应。此外,利用荧光共振能量转移(FRET)的原理,P-CNQDs-CIP用作核黄素(RF)的比率荧光传感器,实现超灵敏的射频检测。PET的组合,厨师,FRET响应机制成功地促进了Ag+的多模式传感,CIP,和RF。检测范围为0.05-100μM,0.002-2μM,和0.05-60μM,相应的最低检测限为17.1nM,1.1nM,和29.2nM,分别。这种多功能传感器已有效地应用于实际样品,包括检测河水和维生素B2片。
The simultaneous detection of multiple analytes through a single fluorescence sensor is highly attractive. In this study, phosphorus-doped graphitic carbon nitride quantum dots (P-CNQDs) were developed, achieving multi-mode sensing through three distinct response mechanisms. The preparation involved using melamine as the carbon and nitrogen source and ammonium dihydrogen phosphate as the phosphorus source. Uniform and narrowly distributed P-CNQDs were successfully synthesized through chemical oxidation and hydrothermal methods, with an average size of 2.4 nm. These unique P-CNQDs exhibited fluorescence quenching through photo-induced electron transfer (PET) in response to Ag+. Additionally, the formation of hydrogen bonds and coordination interactions between P-CNQDs-Ag+ and ciprofloxacin (CIP) led to a pronounced fluorescence response to CIP by the chelation enhanced fluorescence (CHEF) mechanism. Furthermore, leveraging the principle of fluorescence resonance energy transfer (FRET), P-CNQDs-CIP served as a ratio fluorescence sensor for riboflavin (RF), enabling ultra-sensitive detection of RF. The combination of PET, CHEF, and FRET response mechanisms successfully facilitated multi-mode sensing for Ag+, CIP, and RF. The detection ranges were 0.05-100 μM, 0.002-2 μM, and 0.05-60 μM, with corresponding lowest detection limits of 17.1 nM, 1.1 nM, and 29.2 nM, respectively. This versatile sensor has been effectively applied to real samples, including the detection of river water and vitamin B2 tablets.