BLOOD-BASED LATERAL-FLOW DIPSTICK ASSAY FOR DETECTION OF ENTERIC FEVER

摘要

The blood-based lateral-flow dipstick assay for detection of enteric fever is an immunochromatographic dipstick assay based on detection of Salmonella enterica serovar Typhi (S. Typhi) LPS-specific IgG in lymphocyte culture secretion. The dipstick has a test line of an S. Typhi strain antigen extending across a chromatographic stationary phase disposed on a backing, A conjugate pad of glass fibers is attached to the backing so that it overlaps the stationary phase. The conjugate pad is soaked in a first mammal's anti-human antibody (e.g., goat anti-human IgG) conjugated with a color indicator (e.g., colloidal gold nanoparticles exhibiting a wine red color). When dipped in a lymphocyte culture of a human enteric fever victim, the test line turns to the color of the color indicator. A control line of anti-first mammal antibody across the stationary phase changes to the color of the indicator so long as the conjugated anti-human antibody remains viable.