Aim. Construction of test-systems for dot-immunoassay using colloid gold nanoparticles as a marker of specific antibodies for the detection of botulinic toxin in clinical material and food products. Materials and methods. 20 nm gold nanoparticles were used as a marker of specific antibodies. IgGs were isolated from polyvalent diagnostic sera against type А, В, С, E, F botulin toxins produced by SPC Allergen (Stavropol) with 5000 - 10 000 ME activity. Botulin toxin in clinical material (blood sera) from 3 patients with established botulism clinical diagnosis as well as food product (home-made mushroom soup solyanka) was determined by dot immunoassay on nitrocellulose membrane. Results. Botulin toxin was detected in all the studied samples (blood sera from 3 patients and the soup) that was registered in the patient No. 1 at the 1:2112 dilution of fhe studied sample, in patient No. 2 - 1:32, in patients No. 3 - 1:1056, in the food product - 1:8. Botulin toxin was not detected in the negative control (pure cultures of the dysentery cauzative agents and intestine yersinosis, blood sera of the patient with All and a healthy individual as well as canned beans in tomato sauce and canned green peas). Conclusion. A highly sensitive specific test-system was developed for dot-immunoassay based on the commercial anti-botulin antibodies labelled with colloid gold particles that allows to detect botulin toxins within 2 hours in the sample volume of 1 - 2 microlites .

CFU/ml) and soluble antigens (FI) − ≥ 4.8 ng/ml and high specificity, confirmed by the absence of false-positive reactions with five heterologous microorganisms. The test-systems were used for Y. pestis antigen detection in field material from the territory of the Altai mountain natural plague focus by dot-immunoassay with comparison of the received results in passive hemagglutination reaction. Test-systems possessed a number of advantages as compared to routine serological reactions and could be applied with success by practical public health services both in stationary and field conditions.

Aim. Comparison of effectiveness of solid phase methods of immune detection of botulinic toxin in blood sera of a patient with botulism diagnosis: dot-immune assay using specific anti-botulinic antibodies (AT) labeled with nanoparticles of colloid silver, phosphorescent analysis (PHOSPHAN) using streptavidin label with platinum coproporphyrin (PtCP) and polystyrene nanoparticles, containing chelate complex of europium ions with naphthoyl trifluoroacetone (NA-Eu). Materials and methods. Silver nanoparticle labeled IgG isolated from a commercial diagnostic polyvalent sera against type А, В, С, E, F botulotoxins manufactured by SPA Allergen (Stavropol) with 5000 - 10000 IU activity and biotin conjugated commercial monoclonal antibodies against botulotoxin A, polyclonal mono-specific AB against botulotixin В and E and polyvalent immunoglobulin against botulotoxin А, В, С, E, F. Detection ofbotulotoxin in clinical material was carried out in dot-immunoassay on nitrocellulose membrane by PHOSPHAN method in an experimental test system using 2 detector systems based on streptavidin: PtCP and NA-Eu. Results. Botulotoxin was detected in blood sera of the botulism patient using both of the developed immune detection methods. PHOSPHAN method allowed to identify serotype В botulotoxin, that corresponded with the results obtained in botulotoxin biological neutralization reaction. Sensitivity of PHOSPHAN with NA-Eu luminescent nanoparticle based detection system was higher than with PtCP label. Conclusion. The developed methods (PHOSPHAN and dot-immunoassay) differ by high specificity and sensitivity and may be recommended for express detection of botulinic toxin in clinical material.

ФКУЗ Иркутский научноисследовательский противочумный институт Сибири и Дальнего Востока Федеральной службы по надзору в сфере защиты прав потребителей и благополучия человека (664047, г. Иркутск, ул. Трилиссера, 78, Россия)