Fabrication and eva‎luation of optical nano biosensor for nitrate detection and determination

2/19/2024 12:00:00 AM

The presence of pollutants in the environment has irreparable effects and cancer can be mentioned as one of their main risks. Considering that cancer is the second leading cause of death in the world, the first step is to prevent it and improve the food chain. Detection and measurement of pollutants During the last three decades, the presence of nitrogen compounds (including nitrate and nitrite) in the products of the food industry, agriculture and drinking water has been proven and its harmful effects on human life have been investigated. These harmful consequences can be categorized in two areas: health - environment and economy - business. In the first pHase, diseases such as gastrointestinal cancer, blue baby syndrome, Parkinson's and the pHenomenon of overeating have been reported in the water ecosystem. In the second area, consequences such as the contamination of agricultural products and the weakening of aquatic exports due to the presence of nitrates in excess of the permissible limit have been reported. On the other hand, the necessity of timely and accurate detection of chemical pollutants has caused the growth and development of diagnostic methods and sensors. In this research, it was tried to design a nanosensor and a nanobiosensor by optical detection method using layering of gold nanoparticles and immobilization of nitrate reductase enzyme on the glass surface. The size distribution of the synthesized nanoparticles was checked by DLS test and the surface morpHology of the sensors was checked by FE-SEM test. Also, the performance of the sensors was checked using optical spectroscopy (Uv-Vis) test. Finally, the calibration curve of both types of sensors followed a power function (semi-logarithmic). So that the nitrate concentration measurement range for the optimized nanosensor was in the range of 0.05-500 ppm and in this condition the detection limit was calculated as 56 ppb. Also, the optimal nanobiosensor measured nitrate concentration in the range of 0.02-500 ppm with a detection limit of 10 ppb.

نانوزيست حسگر , حسگرنوري , نيتريت , نيترات , حدتشخيص , حساسيت , طيف سنجي نوري

nanobiosensor , optical sensor , nitrite , nitrate , detection limit , sensitivity , optical spectroscopy

Mahyar Cheraghi lame

Alireza Hemmati