The methods of detection of mycotoxins in agricultural products have been analyzed. The advantages of using the fluorescence methods for the express diagnostics of the presence of mycotoxins in samples have been shown. The development of an optical biosensor, which allows the detection of mycotoxins in the field, has been presented. The principles of operation have been established, and the constructive solution of a sensor has been proposed. An electro-optical scheme for obtaining an information signal has been developed and tested. The particular attention has been paid to the choice of an element base of the proposed microsensor. The principles and procedure for its validation have been shown. The practical results of testing the developed technical solution have been presented. The achieved relative error in the linear approximation of the sensor conversion characteristics in the interval of concentrations 0…100 ppb at a temperature of 15…25 °С does not exceed 2%. The developed sensor can be used in agriculture for the express detection and evaluation of the mycotoxin contamination.

The real manifestations of biowarfare were only during local military conflicts. In previous times the danger with this factor forms through activation of terrorist organizations. To prevent non-desirable consequences and to preserve the lives and health of people it is necessary to provide constant control by the application of complex of the new generation of the instrumental devices based on the principles of biosensorics which allow rapid revealing step by step: total toxicity of environmental objects, presence of appropriate groups and specific chemical substances among them. It is demonstrated simple and rapid estimation of the total toxicity through the control of the intensity of chlorophyll fluorescence (IChF) by the direct or remote ways by the device "Floratest" (Ukraine). There is possible on the basis of IChF curve of growing plants from some territory during appropriate period to reveal appearance of toxic substances in this area. Their presence in more local cases may be done by using bioluminescent bacteria (pure Ukrainian strains) or/and controlling short term Daphnia living medium by developed portable chemiluminometer. For the revealing of some groups of toxic elements it is recommended the cerium oxide ISFETs based enzymatic biosensors. The last and devices based on SPR ("Plasmotest", Ukraine), porous silicon (with the registration of biospecific interaction macromolecules by luminescence or electro conductivity) and some nano-metal oxides were realized in immune biosensors at the determination of content of number of mycotoxins, some microorganisms (Salmonella spp.) and diagnostics of viral disease (retroviral leucosis). We present the main characteristics of the above mentioned devices and give confirmation that all the analysis meets practice demands. Overall time of analysis is in range 10 min and it is very simple and may be realized in field conditions.

The immune biosensor are proposed in the lab on a chip form based on the nano-structured silicon for simultaneous analysis of samples number. The procedure of the nano-structured silicon formation and preparation of the photoresistor-test strips have been described and used in case of the cow retroviral leukemia express diagnostics. Keywords -nano-structured silicon; lab on a chip; immune biosensor; diagnostics; retroviral leukemia.I.