Research On Living Stem Cell Biophotonic Detection System

Stem cells have the ability of self-renewal and highly proliferative.They have broad application prospects in regenerative medicine.A large number of stem cells with high viability is the prerequisite for the stem cells' biology research and clinical application.Therefore,it is of great value to study the physiological state of cells in real time.Owing to the sensitive indication of bio-photon radiation on cell physiological state and the label-free and non-invasive properties of optical detection,a bio-photon detection system for living stem cells was designed and built,which can provide a reliable experimental platform for further study of the relationship between bio-photon and the physiological state of stem cells.Our main works are listed as follows:1.According to the ultra weak intensity and non-steady state of bio-photon emission process,a method of bio-photon detection system for living stem cells was proposed based on the single photon counting technology and the multi-channel timing control.2.In this system,Xenon lamp with high voltage was used as light source.Optical fibers and coupling lens were used to design the optical transmission path in order to improve the flexibility of the system.A sample darkroom was designed using food-grade stainless steel to make the cells in dark and avoid sample contamination.A photomultiplier tube with high sensitivity,low noise and fast response was used as detector,which can highly improve the sensitivity and reduce the noise level of the system.3.Aiming at the requirement of timing control for the delayed luminescence detection of living stem cells,a design of multi-channel timing controller based on ARM + FPGA architecture was proposed,and the product design of the instrument was carried out.Based on ARM chip STM32F103ZET6 and FPGA chip EP3C16Q240C8N,the hardware circuit of multi-channel timing controller was designed.Based on this hardware platform,FPGA logic circuit design,ARM software design,touch screen interface design and host computer software design were completed.The timing controller achieved 8-channel parallel output,timing accuracy of 1?s,timing flexibility,dual-channel trigger response and ethernet remote control and other functions.4.Using the multichannel timing controller above as the control center,a bio-photon detection system for living stem cells was built,and a series of bio-photon detection experiments for stem cells were carried out.The experimental results showed that the system has the advantages of high detection accuracy(4.6xl0-5/s·pW,at 600nm),low noise level(dark count under 20 photon/s),short measurement delay time(about 35ms),strong extensibility,high application flexibility,and so on.It can meet the measurement requirements of bio-photon emission from living cells,and thus provide a stable and reliable measurement tool for further study of the relationship between bio-photon emission and the physiological state of stem cells.