DIAGNOSTICUM FOR IDENTIFICATION OF ESCHERICHIA COLI 0157:H7 AND METHOD OF ITS PREPARING Russian patent published in 2002 - IPC

FIELD: medicine, microbiology. SUBSTANCE: invention relates to the development of diagnosticum designated for identification of E. coli 0157:H7 for epidemiological inspection and diagnosis of hemorrhagic colitis. Diagnosticum comprises a carrier and sensitine. As a carrier the diagnosticum comprises polystyrene latex stained by lipid-soluble blue antraquine dye with activated amino-groups having particles size 0.502 mcm, variation coefficient is 4.1-4.5%, dispersion coefficient is 1.003-1.005, concentration of amino-groups is 2.3 x (10^-3 - 10^-4) mole/g and as sensitine the diagnosticum comprises protein A and rabbit immunoglobulins showing specificity raised to polysaccharide fraction LPS 0157 and protein flagellar antigen H7. For preparing the indicated diagnosticum 1-% suspension of preliminary washed out particles used as a carrier of polystyrene latex is incubated with protein A in concentration 55 mcg/ml as a sensitine in their equal ratio 1:1 and then washed out particles are incubated with rabbit specific immunoglobulins raised to polysaccharide fraction of lipopolysaccharide 0157, protein flagellar antigen H7 in concentration 180 mcg and 210 mcg, respectively, in their volume ratio 1:1. After incubation latex particles are treated with glycine buffer at pH 8.2 and incubated repeatedly. The prepared diagnosticum presents 0.5-% suspension of latex particles that are bound covalently with indicated rabbit specific immunoglobulins. Diagnosticum can be used for laboratory diagnosis of hemorrhagic colitis and for identification of E. coli 0157: H7 in foodstuffs. EFFECT: high sensitivity and specificity of diagnosticum. 2 cl, 2 tbl