Research On Hollow Fiber SPR Sensor Available For Microfluidic Chip

Surface plasmon resonance(SPR)sensor,as a novel sensor,is commonly used to measure refractive index with a high sensitivity.It is widely used in biomedicine,drug research and development,environmental monitoring and other fields.With the industry's demand for small dose detection technologies,SPR sensors based on fiber available for microfluidic chips are urgently for research and development.This paper proposes and fabricates an SPR sensor based on hollow fiber,which not only combines SPR with microfluidic channels,but also provides more reference and ideas for the research and application.Compared with microfluidic chips with complicated manufacturing process and high cost,the sensors studied in this paper have simple manufacturing process and low cost,and have broader application prospects in small dose liquid detection.The main research contents are as follows:1.A novel hollow fiber SPR sensor based on the core in the fiber cladding with dual microfluidic channels is also proposed.The hollow fiber is polished,welded and plated gold film and finally fabricated and packaged in capillary and PDMS with two different packaging methods for the liquid refractive index sensing in the two channels.Compared with the microfluidic SPR sensors based on the capillary,the hollow fiber SPR sensor uses hollow fiber which can transmit light beam with single mode,so that the sensitivity is greatly improved and the sensor volume is also reduced.By theoretical simulation,the best gold film thickness and optical fiber grinding angle were determined.After theoretical simulation,we packaged the fiber probe and achieve the liquid refractive index sensing test in the two channels.The two sensing channels of the sensor can work independently,and the refractive index of the liquid in a small dose is detected.Through the comparison of the experimental results,we can see that the inner channel sensitivity of the hollow fiber SPR sensor has about two times of improvement.2.A novel microfluidic surface plasmon resonance sensor based on a hanging-core fiber is also proposed.A single microfluidic channel SPR sensing structure is fabricated using a hollow fiber with suspension core,plated a gold film,for detecting the liquid refractive index detection.The sensor is studied from theoretical simulation and experimental test.The probe is packaged in two different methods to realize the sensing test of the liquid refractive index in the microfluidic channel.The sensing properties of different film thicknesses are studied and the most suitable gold film thickness is determined according to the experimental spectrum.In conclusion,we propose a dual microfluidic channels SPR sensor based on the hollow fiber in this paper,and we combine the small dose detection technology and fiber SPR sensor,and combine with distributed technology,that there are two microfluidic channels;we design a single microfluidic channel SPR based on the hanging core fiber,this is the first time to use the hanging core to produce a microfluidic channel SPR sensing device.