Yu Aoyang, Wang Xiaochen, Ru Chengbo
School of Criminal Science and Technology, Criminal Investigation Police University of China, Shenyang 110035, China; Key Laboratory of Impression Evidence Examination and Identification Technology, Ministry of Public Security, China.
School of Criminal Science and Technology, Criminal Investigation Police University of China, Shenyang 110035, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2023 Dec 15;303:123263. doi: 10.1016/j.saa.2023.123263. Epub 2023 Aug 15.
2,4,6-trinitrophenol (TPA) natural degradation is nearly impossible and its accumulation threatens ecosystem. Optical sensing is an attractive detection method for TPA with low demand of equipment and data processing, but still needs to be improved. This work was dedicated to increasing probe-loading content so as to improve sensing sensitivity. Three probes derived from Eu(III)-benzimidazole were designed, with their active H atoms replaced by alkyl groups to eliminate the hydrogen bond with supporting host and thus to improve probe-loading content. Their molecular structure, absorption, emission, and excitation spectra were discussed to confirm their sensing potential to TPA. Then these three probes were loaded into host (bio-MOF-1) via ionic exchange method, which was confirmed by XRD, N adsorption/desorption, ICP, and SEM. The loading content and sensing performance of these three probes in bio-MOF-1 were compared. It was found that the elimination of active H atoms indeed increased probe loading content from 44% to 78%, with sensing coefficient increased from 0.010 μM to 0.029 μM. A ratiometric sensing towards TPA was observed, with blue emission from bio-MOF-1 host increased and red emission from Eu(III) probe decreased, which was detectable by naked eyes. Linear working equations were fitted with high selectivity.
2,4,6-三硝基苯酚（TPA）的自然降解几乎是不可能的，其积累对生态系统构成威胁。光学传感是一种有吸引力的TPA检测方法，对设备和数据处理的要求较低，但仍需改进。这项工作致力于提高探针负载量以提高传感灵敏度。设计了三种源自铕（III）-苯并咪唑的探针，其活性氢原子被烷基取代，以消除与支撑主体的氢键，从而提高探针负载量。讨论了它们的分子结构、吸收、发射和激发光谱，以确认它们对TPA的传感潜力。然后通过离子交换法将这三种探针负载到主体（生物MOF-1）中，通过XRD、N吸附/脱附、ICP和SEM进行了确认。比较了这三种探针在生物MOF-1中的负载量和传感性能。发现消除活性氢原子确实使探针负载量从44%提高到78%，传感系数从0.010 μM提高到0.029 μM。观察到对TPA的比率传感，生物MOF-1主体的蓝色发射增加，铕（III）探针的红色发射减少，肉眼即可检测到。线性工作方程拟合具有高选择性。
