Abstract

Innovative Microfluidic Isolation of Circulating Biomarkers: cfDNA and Exosomes

Sehyun Shin, Professor & Director, Korea University

Liquid biopsy, non-invasively analyzing biomarkers circulating in various body fluids, has been emphasized as a promising technology to accelerate the realization of personalized treatment of cancer. Among the circulating biomarkers, cell-free DNA (cfDNA) and exosome have been implicated as important biomarkers in cancer management. Efficient techniques for isolation of such biomarkers from blood are prerequisites for precision liquid biopsy. Also, a sample-to-answer system for such biomarker extraction is highly required for clinical application. Thus, in the present study, two of technologies (PIBEX and PLL clustering) to isolate main circulating biomarkers (cfDNA and exosome) of liquid biopsy are presented. First, the PIBEX system is a centrifugation-free cfDNA extraction microfluidic chip capable of extracting cfDNA from plasma samples through microfluidic circuits within 15 min under vacuum pressure using an immiscible solvent. Second, the PLL clustering method is the microfluidic chip capable of isolating exosomes from plasma samples within an hour under vacuum pressure using a cationic polymer solution. These chips effectively eliminates the repetitive centrifugation processes and dramatically shortened the sample preparation time. The proposed microfluidic platform could facilitate the development of a sample-to-answer system for use in liquid biopsy of cancers.