Development Of In-situ Microfluidic Devices For Synchrotron Radiation And Application In Research Of Protein

Synchrotron radiation small-angle X-ray scattering(SR-SAXS) is an advanced technique for investigating the structure of matter and it is widely employed in condensed matter physics, biochemistry, material science and other fields with its unique advantages. Bio-macromolecules in solution, such as protein, is one of the most important research fields of SR-SAXS which can be applied to determine the microscopic structure and conformation at near-physiological conditions. The aim of this thesis is to make further improvement of in-situ experimental ability on solution samples for the small-angle scattering beamline and extend the application of SR-SAXS for structural investigation of bio-macromolecules. In this dissertation, In-situ microfluidic devices for SR-SAXS were developed according to experimental requirements and the application study of these devices in the research of protein was also conducted. The main works were shown as follow:1. A controlled microfluidic peristaltic device was developed. The control system of this peristaltic device was programed with Lab VIEW software. The sample volume and the relationship between solution viscosity and peristaltic rate were calibrated. After being installed on the beamline of SR-SAXS, the validity of reducing radiation damage of this peristaltic device was also verified combined with protein samples. In addition, the hardware and software of this peristaltic device were optimized and updated to improve the performance.2. A temperature-jump microfluidic chip device was developed. The thermal characterization of fluid within the microchannel was analyzed with a computational fluid dynamics software ANSYS CFX. The physical design of microchannel and heater was completed as well as the engineering design based on the numerical simulation results. Fluorescent dye was applied as a temperature indicator to calibrate the rising temperature within this microfluidic device. After that, optimization and improvement was made based on the prototype according to the testing results. In addition, time-resolved SAXS measurement of protein refolding was conducted with the optimized microfluidic device which was installed on the beamline of SR-SAXS.This thesis was started to meet experimental requirements by developing two kinds of microfluidic devices applied in SR-SAXS. It will facilitate the application of SR-SAXS in solution samples measurement and is meaningful for improvement of in-situ experimental ability on solution samples for the small-angle scattering beamline.