Development of a Biotinylated Nanobody-Based Gold Nanoparticle Immunochromatographic Assay for the Detection of Procymidone in Crops

• DOI: 10.1021/acs.jafc.3c03408
• Publication Date: 2023-08-23T18:26:17Z
• Authors: Min-Ling Liu; Xiao-Ting He; Zhen-Lin Xu; Hao Deng; Yu-Dong Shen; Lin Luo; Xing Shen; Zi-Jian Chen; Bruce Hammock; Hong Wang
• Keywords: Streptavidin; Biopanning

A heavy-chain antibody (VHH) library against procymidone (PRM) was constructed via immunizing Bactrian camels. Through careful biopanning, seven nanobodies (Nbs) with different sequences were obtained. The variability in their performance primarily attributed to the amino acid differences complementarity-determining region 3 (CDR3), as analyzed by molecular docking. Nb exhibiting highest sensitivity, named NbFM5, biotinylated and conjugated streptavidin-labeled gold nanoparticles preserve epitope’s activity prevent a decrease sensitivity due traditional random electrostatic adsorption. Subsequently, simple sensitive immunochromatographic assay (ICA) developed for rapid detection of PRM based on (btNb). btNb-ICA showed cut-off value 200 ng/mL visual judgment half-inhibitory concentration (IC50) 6.04 quantitative detection. limit (LOD) low 0.88 ng/mL. recoveries actual samples crops ranged from 82.2 117.3%, aligning well results obtained GC–MS/MS (R2 = 0.995). In summary, demonstrated high specificity good accuracy residues vegetables. total analysis time preparing sample obtaining result less than 25 min.