Details

Autor(en) / Beteiligte

• Luo, Lin
• Lin, Shi-Qi
• Wu, Zhuo-Yu
• Wang, Hong
• Chen, Zi-Jian
• Deng, Hao
• Shen, Yu-Dong
• Zhang, Wen-Feng
• Lei, Hong-Tao
• Xu, Zhen-Lin

Titel

Nanobody-based fluorescent immunoassay using carbon dots anchored cobalt oxyhydroxide composite for the sensitive detection of fenitrothion

Ist Teil von

• Journal of hazardous materials, 2022-10, Vol.439, p.129701-129701, Article 129701

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Fenitrothion (FN) residue in food is a serious threat to public health. Consequently, a sensitive, cost-effective, and convenient immunoassay for FN urgently needs to be fabricated to safeguard human health. Herein, a nanobody-alkaline phosphatase fusion protein (Nb-ALP)-based fluorescent ELISA using red emissive carbon dots (r-CDs) anchored cobalt oxyhydroxide nanosheet (CoOOH NS) composite was developed for detecting FN. Briefly, a Nb-ALP was obtained by autoinduction expression and employed as a recognition, signal transduction, and amplification element. As the fluorescence signal source, r-CDs were assembled with CoOOH NS to yield the r-CDs@CoOOH NS composite, leading to the fluorescence quenching of r-CDs via Förster resonance energy transfer (FRET). After competitive immunoreaction, the Nb-ALP bounded to the immobilized antigen can mediate the production of ascorbic acid, which can reduce the CoOOH NS to Co2+, breaking the FRET between r-CDs and CoOOH NS, accompanied by the fluorescence recovery of r-CDs. This fluorescent ELISA is highly sensitive to FN with a detection limit of 0.14 ng mL−1, which is 25-fold lower than that of conventional colorimetric ELISAs. The recovery test of food samples and the validation by GC−MS/MS further demonstrated the proposed assay was an ideal tool for detecting FN. [Display omitted] •Nanobody-alkaline phosphatase (Nb-ALP) against fenitrothion was prepared.•The red-emissive carbon dots@cobalt oxyhydroxide nanocomposite was prepared.•The nanocomposites as a signaling element have been used for fabricating immunoassay.•A highly sensitive fluorescent ELISA for fenitrothion was developed.