Portable Microsystem For Detecting Antibiotics In Food Based On Fluorescenc

Antibiotics have highly effective antibacterial activity and are widely used in human medical treatment and animal husbandry.However,the abuse of antibiotics is prone to adverse consequences,for example,in animal husbandry,farmers often add veterinary antibiotics to feed to promote animal growth,resulting in antibiotic residues in meat products,egg milk,aquatic products,etc.,which are harmful to human health,and can cause cancer,teratogenicity,sudden onset,etc.Especially when bacteria become resistant to drugs and become "superbugs",conventional antibiotics are difficult to eliminate,which may cause a major public health problem.Therefore,it is important to test for antibiotic residues in food and the environment.Classical detection solutions such as high performance liquid chromatography and gas chromatography are not suitable for daily rapid detection scenarios due to high equipment cost and complex operation.Fluorescent biosensors have become an ideal choice to achieve immediate detection of antibiotic residues because of their high sensitivity,specificity,simplicity and low cost.However,conventional fluorescence detection devices are large,costly,and not suitable for immediate on-site detection,so there is an urgent need to develop portable fluorescence detection devices.At present,the global smartphone device users have exceeded 5 billion people,the popularity is high,and with the increase of sensors integrated in smartphones and processor performance,users can collect and process more information through cell phones,combining smartphones with instant detection can improve the portability of instant detection equipment and reduce the cost of equipment.In this paper,two antibiotic detection schemes are designed: colorimetric and fluorescence methods,for which signal acquisition procedures and signal extraction algorithms are designed,respectively,and also fluorescence collection light paths are designed for the fluorescence detection method.The work in this paper mainly includes the following points:1.A colorimetric biosensor was constructed for the detection of enrofloxacin.The end-extension enzyme amplification reaction was used to amplify the detection signal and improve the detection sensitivity,and a cell phone algorithm was designed to quantify the colorimetric signal of the test strips,achieving a highly sensitive detection of enrofloxacin with a detection limit of 10 μg/L.2.An external fluorescence detection optical path system for smartphones was designed,using an orthogonal optical path structure,selecting suitable optical components,customizing the corresponding support structure using 3D printing technology to match with the cell phone,and designing a smartphone-based fluorescence signal extraction algorithm to identify and quantify the fluorescence signal.The fluorescent biosensor was constructed to specifically identify and quantify chloramphenicol,and the detection range of chloramphenicol was obtained from 0.5 ～2.7 n M by optimizing the experimental conditions.3.The application software for optical signal quantitative detection was developed on Andriod studio development platform,which has good expansibility.Two custom cameras were designed to extract and quantify the colorimetric and fluorescent signals.