Silver Nanoparticles/Bacterial Cellulose Nanofiber Optical Sensor for Determination of 2-Mercaptobenzoxazole

In the present research, an optical sensor based on bacterial cellulose nanofibers (BCNF) film containing silver nanoparticles (AgNP) was fabricated and used for the determination of 2-mercaptobenzoxazole (MBO), which is considered a poisonous and pollutant agent of water. To fabricate nanocomposite, the effective variables in the fabrication process such as pH of the solution, AgNO3 concentration, the mass ratio of Ag to nano paper, temperature, and reaction time was optimized. The results obtained from Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive x-ray Spectroscopy (EDS), Thermal Gravimetry Analysis (TGA), and UV-Vis spectroscopy showed that AgNPs have been successfully synthesized and fixed in the structure of BCNF film. The changes in peak absorption of local surface plasmonic of AgNP to the increase of MBO concentration were considered as an analytic sign. The prepared sensor has a linear range of 5 - 150 μg mL-1 and a limit of detection of 1.7 μg mL-1 for the determination of MBO. To evaluate the selectivity of the sensor, its performance was investigated in the presence of interference compounds. To investigate the practical performance of the sensor to detect MBO, a water sample of Tejan River was evaluated. The results confirmed that the sensor has selectivity ability in the presence of other probable troublesome compounds and is suitable to detect MBO in real samples.