Miniaturized optofluidic label-free cytometry

Flow cytometry has wide applications in cell biology and medicine. Compared with conventional fluorescence labeling, light scattering can be adopted as a label-free cytometric method. Integration of optics with microfluidics, the optofluidic technology may help for the advancement of the next generation miniaturized label-free cytometry. Optofluidic label-free cytometry that can obtain two dimensional light scattering patterns from single cells has been developed. Laser light is fibered-coupled onto a microfluidic chip, and light scattering patterns can be obtained via a CMOS detector. Light scattering from cells or particles in such a cytometric setup can be simulated via the Mie theory or finite-difference time-domain (FDTD) method. The experimental results agree well with the simulated ones for yeast cells. Further development of the optofluidic label-free cytometric technique may help for early cancer screening, and provide portable instruments for clinics and home care.