Development and comparison of immunochromatographic strips with four nanomaterial labels: Colloidal gold, new colloidal gold, multi-branched gold nanoflowers and Luminol-reduced Au nanoparticles for visual detection of Vibrio parahaemolyticus in seafood

In this study, the four nanomaterials: Traditional colloidal gold (AuNP), New colloidal gold (N-AuNP), Multibranched gold nanoflowers (AuNF) and Luminol-reduced Au nanoparticles (L-AuNP) were respectively labeled with the monoclonal antibody against Vibrio parahaemolyticus (V. parahaemolyticus). We aimed to develop lateral flow immunoassays (LFIAs) with these nanomaterial labels and determine their performance in visual detection of V. parahaemolyticus. The results of four colloidal gold particle-labeled LFIAs and polymerase chain reaction (PCR) simultaneously detected in actual samples were to be highly consistent, indicating that strips have high accuracy. The four strips were also found to be stable up to 14 weeks under laboratory conditions. In terms of sensitivity, the N-AuNP-based strip was slightly better than the other three. For the N-AuNP-based strips, the difference between the results obtained for different batches was high consistency, and the stability was much better than that of the AuNP-, AuNF-and L-AuNP-based ones. Our results indicate that the N-AuNP can be better used as labels in immunochromatographic tests. It can also reduce the based antibodies, improve the detection sensitivity and reduce the production cost, thereby expanding the scale of production. The use of LFIA labeled with N-AuNP can be more effective, rapid and inexpensive methods for V. parahaemolyticus assay in on-site applications.

Automated summary

In this study, four nanomaterials were labeled with antibodies against V. parahaemolyticus to develop lateral flow immunoassays (LFIAs) for visual detection. Among them, N-AuNP showed slightly better sensitivity and stability compared to traditional colloidal gold, multibranched gold nanoflowers, and luminol-reduced Au nanoparticles. This suggests that N-AuNP can be a more effective and cost-efficient label for on-site detection of V. parahaemolyticus.