Iranian Research Organization for Science and Technology (IROST) Innovative Food Technologies 2783-350X 8 4 2021 07 23 Fabrication and implementation of a biosensor for health evaluation in raw milk Fabrication and implementation of a biosensor for health evaluation in raw milk 457 468 1074 10.22104/jift.2019.3581.1860 FA Ayat Mohammad-Razdari Ph.D. student, Department of Mechanical Engineering Biosystems, Faculty of Agriculture, Shahrekord University, Shahrekord, Iran Sajad Rostami shahrekord university Zahra Izadi Shahrekord University. Mahdi Ghasemi-Varnamkhasti Associate professor, Shahrekord University Ali A Ensafi Professor, Department of Chemistry, Isfahan University of Technology. Mojtaba Bonyadian Associate Professor, Department of Health and Food Quality Control, Faculty of Veterinary Medicine, Shahrekord University. Journal Article 2019 04 29 The use of veterinary drugs, including antibiotics, leads to their aggregation in livestock products such as meat, milk, and eggs. Therefore, rapid, accurate and economy detection of antibiotics for monitoring of food security is necessary. In the current research, a biosensor based on pencil graphite electrode modified with grapheme and gold nanoparticles for detection of β-lactam antibiotic in milk samples was fabricated. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques for evaluation of surface electrode changes were applied. Under optimal conditions, using the EIS method specified that in the ranges of 1×10-15 to 1×10-5 M, The relationship between charge transfer resistance and the logarithm of antibiotic concentration was linear and the regression equation was y=119x+2600 (R²=0.977). The current peaks in three measures were achieved as 18, 19.5 and 19 µA. calculation of relative standard deviation (RSD=3.31%) that indicated an acceptable repeatability for biosensor. For investigating of reproducibility, RDS for current peaks was 8.94% that showed a good reproducibility for biosensor. The selectivity of a biosensor in the presence of three antibiotics including streptomycin, tetracycline, and sulfadiazine was checked. Data of charge transfer resistance was indicated that biosensor has non-significant the response towards the other antibiotics. The results showed that biosensor response decreased by 6% after 18 days compared with the first day, which indicates good stability for biosensor. The percentage recovery range for milk samples at concentrations of 1 × 10-9 and 1× 10-11 M for two samples of cow and sheep milk was obtained as 92.3 to 104% in three replications, which indicates an acceptable recovery range for proposed biosensor. The use of veterinary drugs, including antibiotics, leads to their aggregation in livestock products such as meat, milk, and eggs. Therefore, rapid, accurate and economy detection of antibiotics for monitoring of food security is necessary. In the current research, a biosensor based on pencil graphite electrode modified with grapheme and gold nanoparticles for detection of β-lactam antibiotic in milk samples was fabricated. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques for evaluation of surface electrode changes were applied. Under optimal conditions, using the EIS method specified that in the ranges of 1×10-15 to 1×10-5 M, The relationship between charge transfer resistance and the logarithm of antibiotic concentration was linear and the regression equation was y=119x+2600 (R²=0.977). The current peaks in three measures were achieved as 18, 19.5 and 19 µA. calculation of relative standard deviation (RSD=3.31%) that indicated an acceptable repeatability for biosensor. For investigating of reproducibility, RDS for current peaks was 8.94% that showed a good reproducibility for biosensor. The selectivity of a biosensor in the presence of three antibiotics including streptomycin, tetracycline, and sulfadiazine was checked. Data of charge transfer resistance was indicated that biosensor has non-significant the response towards the other antibiotics. The results showed that biosensor response decreased by 6% after 18 days compared with the first day, which indicates good stability for biosensor. The percentage recovery range for milk samples at concentrations of 1 × 10-9 and 1× 10-11 M for two samples of cow and sheep milk was obtained as 92.3 to 104% in three replications, which indicates an acceptable recovery range for proposed biosensor. https://jift.irost.ir/article_1074_708f3cf8100d5e71834b1db77dfa15d6.pdf