Scholarlink

<p>Aflatoxins still pose severe risks to public health due to their high toxicity and carcinogenicity. Herein, we present a novel dual-mode enzyme cascade-amplified immunoassay (ECAIA) for the ultrasensitive and reliable detection of aflatoxins. In this strategy, a nanobody-alkaline phosphatase fusion protein (VHH2-5-AP) was expressed and served as antigen surrogate to compete binding with aflatoxins towards antibody. Bovine serum albumin-gold nanoclusters (BSA-Au NCs) was synthesized and applied as a peroxidase mimic, catalyzing the oxidation of 3,3’,5,5’-tetramethylbenzidine (TMB) into its oxidized form (ox TMB), leading to a reduction in fluorescence due to the inner filter effect. VHH2-5-AP could hydrolyzes L-ascorbic acid-2-phosphate (AAP) into ascorbic acid (AA), thus preventing TMB oxidation and restoring BSA-Au NCs’ fluorescence. In the presence of aflatoxins, less VHH2-5-AP would be captured, leading to oxTMB accumulation and fluorescence quenching. The proposed ECAIA achieved a limit of detection (LOD) of 0.04 ng/mL for colorimetric detection and 0.24 ng/mL for fluorescence detection with high selectivity for aflatoxins. Moreover, the assay exhibited excellent performance in complex food matrices, achieving recoveries between 84% and 116%, which underscores its considerable potential for practical applications in food safety monitoring.</p> Graphical Abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Gold nanoclusters-mediated enzyme cascade-amplified immunoassay for dual-mode sensing of aflatoxins

  • 期刊论文

  • 发表日期：

    2026年5月23日

查看全文
  • Bing Guo,
  • Yuefan Yang,
  • Gege Yu,
  • Ye Wang,
  • Xiaohui Du,
  • Juane Dong,
  • Yanru Wang

摘要

Aflatoxins still pose severe risks to public health due to their high toxicity and carcinogenicity. Herein, we present a novel dual-mode enzyme cascade-amplified immunoassay (ECAIA) for the ultrasensitive and reliable detection of aflatoxins. In this strategy, a nanobody-alkaline phosphatase fusion protein (VHH2-5-AP) was expressed and served as antigen surrogate to compete binding with aflatoxins towards antibody. Bovine serum albumin-gold nanoclusters (BSA-Au NCs) was synthesized and applied as a peroxidase mimic, catalyzing the oxidation of 3,3’,5,5’-tetramethylbenzidine (TMB) into its oxidized form (ox TMB), leading to a reduction in fluorescence due to the inner filter effect. VHH2-5-AP could hydrolyzes L-ascorbic acid-2-phosphate (AAP) into ascorbic acid (AA), thus preventing TMB oxidation and restoring BSA-Au NCs’ fluorescence. In the presence of aflatoxins, less VHH2-5-AP would be captured, leading to oxTMB accumulation and fluorescence quenching. The proposed ECAIA achieved a limit of detection (LOD) of 0.04 ng/mL for colorimetric detection and 0.24 ng/mL for fluorescence detection with high selectivity for aflatoxins. Moreover, the assay exhibited excellent performance in complex food matrices, achieving recoveries between 84% and 116%, which underscores its considerable potential for practical applications in food safety monitoring.

Graphical Abstract