Integration of a microfluidic chip and a photonic crystal for measuring rat C-reactive protein
|關鍵字:||微流道晶片;免標定生物感測器;波導光柵;光子晶體;大鼠C反應蛋白;酵素免疫分析法;microfluidic chip;label free biosensor;resonant waveguide grating;photonic crystal;rat C-reactive protein;ELISA|
In this work, we integrated a photonic crystal with a microfluidic chip as a biosensing platform. This platform comes with a blood cells filtration component; hence, whole blood detection is possible without additional centrifugal process. Regarding the detection system, guided-mode resonance filter (or photonic crystal, PC) was chosen for label-free detection of rat C-reactive protein. When biomolecules are adsorbed on the photonic crystal structure surface, the resonant wavelength shifts due to the change of the refractive index at the surface. Through monitoring the shift of the resonant wavelength, the concentration of C-reactive protein can be determined. Whole blood and serum from rat were used to demonstrate the capability of the device and the results were compared with those from ELISA. The results indicate that the proposed integrated system was able to meaure the rat C-reactive protein accurately from both samples; however, the ELISA can only obtain accurate result from serum sample. To further demonstrate the filtration function, the samples were injected from the outlet of the chip such that the sample did not go through the filter region. The measured concentration is much higher than those obtained when the samples were injected from the inlet and went through the filter region before reaching the PC sensor, due to the nonspecific binding of the cells with the PC sensor. This further demonstrates that our system can effectively work with whole blood samples.
|Appears in Collections:||Thesis|