Ferrous Tungstate Nanomaterials with Excellent Enzyme-Mimicking Activity to Enhance Lateral Flow Immunoassay Sensitivity
Xianqing Tang, Hua Zhang, Jinghuang Chen, Donghui Wu, Yibin Wang, Jian Sun, Zhenxin Wang, Xiurong Yang
Abstract
Lateral flow immunochromatography (LFIA) with gold nanoparticles (AuNPs) is widely used in the biomedical field as a rapid and simple in vitro detection technique. However, the conventional AuNP-LFIA has limitations in sensitivity and detection range. In this study, nonprecious metal iron-based bimetallic FeWO 4 nanomaterials with convenient and excellent enzyme-mimetic catalytic activities were synthesized by a one-pot hydrothermal method. Here, FeWO 4 nanomaterials were combined with C-reactive protein (CRP) detection antibodies to form a novel signal-enhancing probe for the analysis of CRP. The probe further achieves significant signal amplification by catalyzing the oxidation reaction of 3-amino-9-ethylcarbazole in the LFIA assay, thereby improving the sensitivity and accuracy of the assay. The application of FeWO 4 -based LFIA improved the limit of detection of CRP to 19.38 ng/mL after catalytic amplification, which is approximately 30-fold lower than that of the conventional AuNP-LFIA method. In addition, the method demonstrated good stability and reproducibility, providing a promising and prospective strategy for the early diagnosis of inflammatory diseases.