Yan Wu,Yue Zhou,Hongchen Long,Xiangyu Chen,Yuanyuan Jiang,Lei Zhang,Tao Le
The study investigates a bimetallic organic framework (Zn/Eu-MOF) based fluorescent probe for visual detection of ofloxacin (OFL) in pork, beef and fish. The developed sensing probe recognizes OFL through internal filtration and cation-π interaction between OFL and Zn/Eu-MOF, resulting in a distinct color change from orange-red to light green. The content of OFL can be determined through RGB analysis by a mobile-phone. The developed sensing probe offers several advantages such as broad linear range (0.1 ∼ 80 μM), rapid response time (30 s), low detection line (0.44 μM). The effectiveness of the sensing probe can last for five rounds with good recovery. Moreover, the application of the sensing probe on pork, beef and fish samples are reliable, with recoveries ranging from 93.4 to 112.1%, and the relative standard deviations (RSD) within 1.17% to 2.06%. These results suggest that the developed sensing probe could have significant potential for practical on-site test in food.
Yue Li,Ping Liu,Xiaoxue Han,Longyu Guo,Haiyan Jiang,Yongchao Ma
A heterojunction with g-C 3 N 4 @Zn/Eu-MOF covalent interface was synthesized. • g-CN@MOF can be used for photocatalytic degradation and fluorescence detection of ofloxacin. • Efficient removal of ofloxacin in milk by g-CN@MOF foam. • g-CN@MOF can detect ofloxacin residues in milk through smartphone-assisted color recognition. Ofloxacin (OFL) is widely used in medicine and animal husbandry, and its residues in milk raise substantial food-safety concerns. Herein, a dual-functional covalently coupled g-C 3 N 4 @Zn/Eu-MOF composite (g-CN@MOF) was constructed through a one-pot hydrothermal route. FTIR and XPS analyses indicated the formation of C N C O linkages between g-C 3 N 4 and the MOF, yielding an interfacially coupled type-II heterojunction that promoted charge separation. The optimized g-CN@MOF-30 achieved 69.21% removal of 10 mg L −1 OFL within 120 min under visible light, with •O 2 − and •OH identified as the dominant reactive species. Meanwhile, the fluorescence intensity ratio F 440 /F 595 showed a linear response to OFL over the range of 0–100 μM, affording a detection limit of 0.011 μM through an IFE-dominated ratiometric sensing mechanism. After immobilization in sodium alginate foam, the composite exhibited convenient recyclability and enabled OFL removal from pretreated milk samples, while smartphone-based RGB analysis provided rapid visual semi-quantification with recoveries ranging from 100.3% to 109.9%. Download: Download high-res image (269KB) Download: Download full-size image
危险品化学品经营许可证（带存储）