Dataset Information

Nanobody-Based Sandwich Immunoassay for Pathogenic Escherichia coli F17 Strain Detection.

ABSTRACT: Rapid and specific detection of pathogenic bacteria in fecal samples is of critical importance for the diagnosis of neonatal diarrhea in veterinary clinics. Nanobodies are a promising tool for the treatment and diagnosis of infectious diseases due to their unique recognition properties. In this study, we report the design of a nanobody-based magnetofluorescent immunoassay for the sensitive detection of pathogenic Escherichia coli F17-positive strains (E. coli F17). For this, a camel was immunized with purified F17A protein from F17 fimbriae and a nanobody library was constructed by phage display. Two specific anti-F17A nanobodies (Nbs) were selected to design the bioassay. The first one (Nb1) was conjugated to magnetic beads (MBs) to form a complex capable of efficiently capturing the target bacteria. A second horseradish peroxidase (HRP)-conjugated nanobody (Nb4) was used for detection by oxidizing o-phenylenediamine (OPD) to fluorescent 2,3-diaminophenazine (DAP). Our results show that the immunoassay recognizes E. coli F17 with high specificity and sensitivity, with a detection limit of 1.8 CFU/mL in only 90 min. Furthermore, we showed that the immunoassay can be applied to fecal samples without pretreatment and remains stable for at least one month when stored at 4 °C.

SUBMITTER: Dhehibi A

PROVIDER: S-EPMC9953962 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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Nanobody-Based Sandwich Immunoassay for Pathogenic Escherichia coli F17 Strain Detection.

Dhehibi Asma A Allaoui Abdelmounaaim A Raouafi Amal A Terrak Mohammed M Bouhaouala-Zahar Balkiss B Hammadi Mohamed M Raouafi Noureddine N Salhi Imed I

Biosensors 20230220 2

Rapid and specific detection of pathogenic bacteria in fecal samples is of critical importance for the diagnosis of neonatal diarrhea in veterinary clinics. Nanobodies are a promising tool for the treatment and diagnosis of infectious diseases due to their unique recognition properties. In this study, we report the design of a nanobody-based magnetofluorescent immunoassay for the sensitive detection of pathogenic Escherichia coli F17-positive strains (E. coli F17). For this, a came ...[more]

PMID: 36832065

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Nanobody-Based Sandwich Immunoassay for Pathogenic Escherichia coli F17 Strain Detection.

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Nanobody-Based Sandwich Immunoassay for Pathogenic <i>Escherichia coli</i> F17 Strain Detection.

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