Cytometry has wide applications in biomedicine for cell differentiation or disease monitoring. Here we report our newly developed two dimensional (2D) light scattering static cytometric technique for single and multiple cell analysis. The static cytometer adopts a scanning fiber probe for cell excitation and obtains 2D light scattering patterns on a complementary metal oxide semiconductor (CMOS) detector. Our results show that experimental 2D light scattering patterns obtained from single yeast cells are with fringe structure while those from multiple yeast cells give speckle patterns. The experimental results compare favorably with our 2D light scattering Mie theory simulations for both single and multiple cells. The varying of 2D light scattering patterns with different yeast cell clusters, either number or distribution changes, shows the potential of our 2D light scattering static cytometer for cellular diagnostics.
Conventional methods for cervical cancer screening usually employ microscopic observations that may require
fluorescence labeling of the cells, which could be time-consuming and expensive. Development of a novel method for
cervical cancer cells determination in a rapid, label-free manner may significantly improve the cervical cancer screening
technique. Here two-dimensional (2D) light scattering patterns are obtained from yeast cells on a CMOS chip, where
laser light is used to excite single cells via fiber-coupling under a microscope. Good agreements between the
experimental and Mie theory simulation results convey that 2D light scattering patterns from cervical cancer cells may be
obtained upon the apparatus developed here. Mie theory simulations on simplified normal and cancerous cervical cells
show that side scattering spectrum may be used for cervical cancer cells screening. Future experiments further
convincing the 2D light scattering method proposed here may bring up a powerful technique that has profound
applications in cervical cancer cell determination.
Correlation techniques are widely used to extract spectral information from light scattering and other stochastic
processes. Within the photon correlation system, the correlating operation must work at a high speed. In this paper, a
photon correlator based on microcontroller C8051F was developed. In the photon correlator, the work of counting and
scratch is completed by the two 4-bits binary adder 74F161, which is connected to form an 8-bits adder., and the
correlation operation of every channel is carried out by the software of C8051F. By probably choosing high speed
devices counting of 10ns in width pulses can be counted. The correlation operations including multiplying and addition
operation of 56 channels with the circulation program within 3μs were made in interrupt service routine of the C8051F.
The work in this paper can be applied in the ultra-fine particle sizing with photon correlation spectroscopy.