[Detection of staphylococcus aureus exotoxin by nanobiosensor designing with anti body-linked nanosilica]

ABSTRACT

We are no longer able to detect the toxins produced in food products using the traditional techniques. This is due to the fact that the isolation time for food products is not cost-effective and even in most of the cases. Hence with the advent of nanotechnology, the design of selective and smart sensors is one of the greatest industrial revelations of the quality control of food products. This was an laboratory experimental study. In this technique, based on the bacterial antibody connection to nanoparticle, a sensor was used. In this part of the research, as the basis for absorption for the recognition of bacterial toxin, medium sized silica nanoparticles of 10 nano meter in form of solid powder were utilized with Notrino brand. Then the suspension produced from agent-linked nanosilica which was connected to bacterial antibody was positioned near the samples of distrilled water, that were contaminated with Staphylococcus aureus bacterial toxin with the density of 10-3, so that in case any toxin exists in the sample, a connection between toxin antigen and antibody would be formed. Finally, the light absorption related to the connection of antigen to the particle attached antoibody was measured using spectrophotometry. The results indicate that the sensor, up to 10-4 of density is detectable. Additionally, the sensitivity of the sensors were examined after 60 days, the sensor by the 56 day had confirmatory results and started to decrease after those time periods. Nano-particles have unique property in bioanalysis. They have high speed and high sensitivity along with cost effectiveness