PHÁT TRIỂN QUE THỬ PHÁT HIỆN BÀO TỬ BACILLUS ANTHRACIS THEO NGUYÊN LÝ KẾT TỤ MIỄN DỊCH

Tóm tắt

Bacillus anthracis represents a serious threat of biological weapons, and there is an urgent need to
develop a rapid, simple and sensitive assay to detect B. anthracis spores in environmental samples.
Commercial lateral flow immunoassays for detection of B. anthracis spores are easy to perform but
exhibit very low sensitivity. This study aims to develop a sensitive and simple dipstick test, based on
agglutination reaction between B. anthracis spores and antibody-coated magnetic particles, to detect
spores of this pathogen. To this aim, factors affecting the test performance including antibody,
nitrocellulose membrane type, incubation time and pH of reaction between detection conjugate and
sample, and concentration of Tween-20 were optimized. Under the optimal condition (monoclonal
antibody to Anthrax Spore Specific 23A-14G9, UniSart® CN95 nitrocellulose membrane, 30 minutes of
incubation, pH 9.0, and 1% Tween-20), the developed test could detect B. anthracis spores with the
limit of detection of 6 × 104
spores/mL, and showed no cross-reactivity to B. thuringiensis, B. cereus, B.
subtilis, B. clausii, Yersinia bercovier và Yersinia rohdei and E. coli. When applied to detect B.
anthracis spores in simulated starch samples, the developed assay has a detection limit of 107
spores/g
starch. This new immunoassay is particularly suitable for screening of B. anthracis spores in powdery
samples because of its simplicity and improved sensitivity.