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Published on: June 28, 2024
Simple and sensitive fluorescence sensor for methotrexate detection based on the inner filter effect of N, S co-doped
Yanan Zhao1, Shiying Zou2, Danqun Huo3
1Key Laboratory for Biorheological Science and Technology of Ministry of Education, State and Local Joint Engineering Laboratory for Vascular Implants, Bioengineering College of Chongqing University, Chongqing, 400044, PR China.
Abstract:
Reliable and simple detection methods for chemotherapeutic agent contaminants, such as methotrexate, are required to minimize their possible toxic threat. However, detecting them remains a challenging in environmental and biological analysis. Here, we developed a fluorescent N, S co-doped carbon quantum dots (N, S co-doped CQDs) probe to detect methotrexate on the basis of the inner filter effect of fluorescence. Under optimized conditions, the fluorescent probe exhibits high sensitivity and specific selectivity with a linear detection range from 0.4 μg/mL to 41.3 μg/mL and a low detection limit of 12 ng/mL (S/N = 3). Further, this N, S co-doped CQDs fluorescent probe can be used to analyze extracellular fluids and wastewater samples satisfactorily, thereby showing a remarkable potential for broad applications in biological molecule determination and environmental analysis.
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