Preparation Of Optical Coding Materials And Application Research In Mycotoxins

In recent years,the problem of food pollution has become increasingly prominent,seriously threatening the health of the people.Among them,mycotoxins,as an important source of pollution,have attracted more and more attention because of their strong toxicity,trace amount,variety and wide distribution.The current detection methods mainly include high performance liquid chromatography,liquid chromatography-mass spectrometry,enzyme-linked immunosorbent assay,etc.These methods can achieve accurate and sensitive detection purposes,but the experimental instruments are huge,the operation steps are cumbersome,and only one sample can be detected at a time.,cannot meet the needs of instant flux detection.Therefore,it is necessary to establish an accurate,rapid and portable mobile detection platform for mycotoxin.Based on the optically encoded material upconversion nanoparticles and photonic crystal,portable detection platform for mycotoxins based on smart phones was constructed.The main research contents are as follows:1.Preparation of two optically encoded materials: upconversion nanoparticles and photonic crystal:Preparation of upconversion nanoparticles of red,green and blue based on solvothermal method,uniform particle size,high luminescence intensity,and different fluorescence emission spectra;encapsulation of magnetic particles and upconversion nanoparticles with polystyrene by self-healing encapsulation method,used as a coded signal to achieve the purpose of simultaneously detecting three different mycotoxins;Based on monodisperse silica and polymethyl methacrylate nanoparticles,self-assembly forms a photonic crystal template.The internal particles of the template are arranged in order and the appearance is bright.Combined with hydrogel,the anti-opal structure is prepared.Which is for connecting components that can specifically identify the test analysts,and it is a good material for achieving naked eye detection;2.Using the coding material to build a smartphone-based mycotoxin detection platform.The indirect immune competition reaction is performed by upconversion coded microspheres,and the encoded image signal and the detected image signal can be conveniently captured by the portable device and the smart phone;the image is analyzed by the team's own programming Android application,and the HSV-based image recognition mode has more picture information compared with the traditional way,which could provide the reliable and accurate results in less than 1 minute;By using the special properties of photonic crystals with photonic band gaps,when the concentration of the analyte is different,the macroscopic colors exhibited by the films are different.We used a smartphone to record this change with the help of a portable microscope and used a self-programming algorithm to extract the H value of the image to obtain a quantitative analysis of the mycotoxin concentration.The results show that the platform is accurate and fast,and can also be used for the analysis of other objects to be inspected.In summary,based on the optical coding materials,combined with the portability and powerful features of smart phones,this paper constructs a portable detection platform for mycotoxin based on image processing.