SPR Detection Microfluidic Chip Based On Microstructured Optical Fibe

Microfluidic chips with surface plasmon resonance(SPR)as the detection principle have the advantages of high detection efficiency,real-time monitoring and low sample consumption.It is widely used in biochemical detection.However,the current SPR detection microfluidic chips have problems such as the inability to meet multiple detection needs on the same chip,complex to integration,and difficulty in further reducing the size.In order to solve these problems,this paper proposes a solution to construct optical fiber SPR detection microfluidic chips using micro-structured optical fibers.This solution can realize multichannel multi-function detection,and transfer microfluidic technology from chip to optical fiber,and gradually make SPR detection microfluidic chips more multi-functional and allfiber-based.It can also further reduce the volume of microfluidic chips,improve the throughput and production flexibility of microfluidic chips.The specific work content of this article is:(1)In order to solve the problem that it is difficult to meet multiple detection needs on the same SPR detection microfluidic chip,this paper proposes a multi-functional microfluidic chip which is integrated with optical fiber SPR sensors.The chip is integrated with a microfluidic device made of Polydimethylsiloxane(PDMS)by SPR detection unit based on dumbbell fiber,which has two open pores,and the detection channel can form two independent sensing areas,and can realize the integration of multiple detection functions on the same optical fiber by modifying different functional materials in different sensing areas.Finally,three operating modes are integrated on the chip,namely high refractive index substance detection,double parameter detection and temperature compensation.The proposal of this chip solves the problem of single detection function of optical fiber SPR detection microfluidic chip.(2)In order to simplify the integration process of optical fiber composite SPR detection microfluidic chip,in this paper,microfluidic chips are all-fiberized,and a single-channel allfiber SPR detection microfluidic chip is proposed.The SPR detection unit and microfluidic channel of the chip are provided by D-shaped optical fiber,and the SPR sensing area is constructed on the designed D-shaped multimode optical fiber,and it is nested in the quartz tube to form a semi-cylindrical microfluidic channel,which can complete the production of the chip without complex integration process.Subsequently,the surface of the SPR sensing area was sensitized and specifically modified,and the specific detection of cytokine,was realized on this chip.This chip not only simplifies the manufacturing process of microfluidic chips,but also further reduces the volume and sample consumption of microfluidic chips.(3)In order to further improve the detection efficiency of microfluidic chips on the basis that they have been all-fiberized,this paper proposes a multi-channel all-fiber SPR detection microfluidic chip based on space division and wavelength division multiplexing technologies.The microfluidic channels of the chip are provided by the two air channels of the side hole fiber,and the SPR detection unit is made of dumbbell fiber whose core is exposed to air and packaged by fiber micromachining technology.The internal dual-channel of the optical fiber constructed of the side hole fiber and dumbbell fiber can detect two substances separately in space division mode and simultaneously in wavelength division mode.This solution realizes multi-parameter detection on the basis of the chip has been allfiberized,improves the utilization rate of the detection channel,and further improves the detection efficiency of the chip.