Research On Optical Fiber Hemolysis Detection Technology Based On Evanescent Wave

Blood circulates in the heart and capillaries of the human body to meet the basic needs of the human body.The red blood cells in the blood will be destroyed due to the disease or other reasons in the human body,resulting in the overflow of hemoglobin,which is hemolysis.The immediate determination of hemolysis can accurately and effectively diagnose the emergence of diseases.The most important thing in hemolysis determination is to ensure the rapid separation of free hemoglobin and and red blood cells and the accurate determination of their content.However,the existing hemolysis measurement methods have some problems,such as complex process and external pollution.Therefore,it is of great significance to carry out hemolysis measurement efficiently,accurately and without pollution.Optical fiber evanescent wave biosensors have many advantages such as label-free,strong real-time performance,and anti-EMI.It is not affected by biological elements other than evanescent wave field on the surface of fiber core,and has ultra-high detection sensitivity.Therefore,a new hemolysis detection scheme based on optical fiber evanescent wave measurement is designed in this paper.The main research contents are as follows:Firstly,the malady of the current monocrystalline silicon filtration method are analyzed,and the monocrystalline silicon filter is designed to remove the disadvantages of the current monocrystalline silicon filtration method.Secondly,according to the principle of optical fiber evanescent wave sensing,the multi-mode optical fiber is tapered by carbon dioxide laser welding machine,and then combined with microfiltration chip and protective shell to form an optical fiber evanescent wave hemolysis detection sensor.Finally,the optical fiber evanescent wave hemolysis detection system is built.The spectral data is collected through the control circuit with FPGA as the core chip,and the spectral data is solved by the intensity demodulation algorithm,so as to obtain the hemoglobin concentration quickly and accurately.According to the above research contents,the accuracy of hemoglobin content in blood measured by the experiment reached 10 mg / L.Due to the deviation between the actual dilution degree and the ideal dilution degree when preparing hemoglobin solutions with different concentrations for artificial hemolysis,the maximum measurement error between the measured concentration and the actual concentration is 9.35%.