The Research And Design Of Multi-wavelength Portable Immunofluorescence Quantitative Detection System

Technology is like a double-edged sword,which brings benefits to people’s lives but also brings many disadvantages.For example,the harm caused by new technologies for producing and processing food is becoming more and more prominent,mainly involve illegal additions and frequent food pollution incidents.At present,food safety detection methods include high performance liquid chromatography,gas chromatography-mass spectrometry,enzyme-linked immunosorbent assay,colloidal gold immunochromatography,and immunofluorescence.Among them,the immunofluorescence method has high sensitivity,simple labeling,no pollution,in addition,the method combined with the test strip has lower cost.At present,Considering that the fluorescent dyes used in the test strips made by different manufacturers and research institutes are different,and the required excitation light and fluorescence filters are different,in addition,the current immunofluorescence quantitative detector can only detect a single fixed wavelength test strip.If the test strips marked with different fluorescent dyes are used,multiple immunofluorescence quantitative detectors are required,which leads to high price.therefore this paper aims to design and develop a portable,cost-controllable,and accurate quantitative A multi-wavelength portable immunofluorescence quantitative detection system for the detection of samples labeled with different fluorescent dyes.The specific work is as follows:1)According to the diversity of fluorescent dyes mentioned above and the shortcomings of the current immunofluorescence quantitative detector designed for a single wavelength,creatively design optical path structure include ring LED light,turntable filter wheel,lens,CMOS image sensor,the excitation light wavelength range is 380～750nm,and the central wavelength of the fluorescence filter is 380 nm,410nm,525 nm,595nm,610 nm,620nm,in this way,multi-wavelength detection of test strips marked with different fluorescent dyes is realized.2)According to the system design index,using NX12.0 3D modeling software to design a portable mechanical structure system scheme,including internal modules and the external interface reserved for the system shell panel;then according to the mechanical structure scheme,design the main control board based on STM32F103RET6,it includes light source control circuit,stepping motor drive circuit,limit switch control circuit,serial communication circuit,wireless transmission circuit,human-computer interaction and power supply circuit.After completing the hardware and mechanical structure of the system,in order to realize the automatic and intelligent operation of the system,design the control software based on STM32 immunofluorescence quantitative detection system,based on MFC immunofluorescence quantitative detection system software,fluorescence detection data management system based on My SQL,in order for the operator to operate the system conveniently and quickly,the security and stability of the detection data can be ensured and computer resources can be saved.3)In view of the characteristics of the immunofluorescence image detection line and the quality control line,the positions are relatively fixed,the shape is a horizontal narrow strip,and the color difference between the background area and the immunofluorescence complex area is obvious,a method of localization of immunofluorescence complexes based on flood water filling is proposed,which can locate and label the immunofluorescence complexes,and calculate the gray value of the target area,it guarantees the accuracy of detection data,at the same time,1 to 3 test strips are tested to ensure the flexibility of the algorithm.4)After completing the software and hardware design and installation,first complete the test of each module and the concentration calibration experiment of aflatoxin B1,zearalenone and ochratoxin A to verify the feasibility of the system;then test its accuracy,repeatability,stability,etc.Through the above design,the system has the advantages of portability,simple operation,low cost,and the test strips labeled with different fluorescent dyes are detected,according to the concentration calibration experiment,it is verified that the system has a good linear relationship,and the fitting degree is as high as 97%,the relative error is less than 5%,and the repeatability coefficient of variation is less than 2%,all of its indicators meet the expected indicators.Compared with the existing instruments,it not only has wider applicability,but also has great advantages in cost and has broad prospects.