Abstract

Sequential Trapper for Rare Cell Isolation, Detection and Investigation

Tian Fook Kong, Research Fellow , NTU

Cancer is the abnormal growth of cells in the body, which claimed more life than AIDS, tuberculosis, and malaria combined. Early detection and diagnosis of cancer greatly increases the success rate of effective treatment and chances of survival. The presence of these low-abundance rare cells in the peripheral blood indicates the occurrence of cancer metastasis. While being instrumental to the success of early metastatic cancer detection, recovering these rare cells from a patient’s peripheral blood is like finding a needle in a haystack. However, with the advancement in microfluidics and lab-on-a-chip technology, the isolation and detection of rare cells are made possible by exploiting the dissimilarity in cell properties. The main challenges faced in rare cell isolation are in obtaining a high capture efficiency and high-level of statistical confidence for the detection of rare cells due to its low abundance nature. The primary research focus of this project is in the realization of a rapid, sensitive, robust, and inexpensive microfluidics rare cell isolation device. In this work, we developed an innovative sequential rare cell isolation device with up to 100 % trapping yield and > 95 % sequential isolation efficiency, through a series of micro-trappers arranged in a novel arrangement. These trappers comprise of semicircular arcs spaced at specific offsets and distance apart. We introduced two offset parameters in the trapper design – the flow offset and trapper offset, to dictate the desired trajectories of the cells for efficient sequential trapping. We performed a series of parametric study to investigate the trapping characteristics of polystyrene microbeads, and subsequently with a human breast cancer cell line.