Electrochemiluminescence immunoassay strategies based on a hexagonal Ru-MOF and MoS2@GO nanosheets: detection of 5-fluorouracil in serum samples

• Published in: Analyst (London) 2023-04, Vol.148 (8), p.1694-1702
• Main Authors: Ma, Guoyu, Lu, Peng, Zhang, SunXiaoYi, Wu, Kang, Deng, Anping, Li, Jianguo
• Format: Article
• Language: English
• Subjects: Antigens; Dicarboxylic acids; Dichlorides; Electrochemiluminescence; Electron transfer; Electrons; Emitters; Immunoassay; Immunosensors; Metal-organic frameworks; Molybdenum disulfide; Nanosheets; Piezoelectricity; Ruthenium; Ruthenium compounds
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/d3an00190c

Herein, a competitive-type electrochemiluminescence immunosensor for ultrasensitive detection of 5-fluorouracil (5-FU) was fabricated. Ruthenium(ii)-metal–organic framework (Ru-MOF) nanosheets were selected to act a promising ECL luminophore using tris(4,4′-dicarboxylic acid-2,2′-bipyridyl) ruthenium(ii) dichloride (Ru(dcbpy)32+) as the organic ligand. The two-dimensional (2D) Ru-MOF nanosheets achieved an increased loading of Ru(dcbpy)32+ and effectively prevented leakage of the ECL emitter during application, which exhibited satisfactory ECL performance. Thin two-dimensional MoS2@GO was used to modify the electrode as the sensing platform for improving the electron transfer rate and loading more 5-FU coating antigens due to its large specific surface area and piezoelectric catalytic efficiency. Under the optimized conditions, the proposed immunosensor presented high sensitivity, a wide detection range (0.0001 ng–100 ng mL−1), a low limit of detection (0.031 pg mL−1, S/N = 3), good specificity and stability. Furthermore, the immunosensor was successfully applied for the detection of 5-FU in human serum samples with satisfactory results, proving this strategy has potential applications in bioanalysis and clinical diagnosis.