A sample-to-answer droplet magnetofluidic assay platform for quantitative methylation-specific PCR
Dysregulation of DNA methylation has been identified as an epigenetic biomarker for numerous cancer types. Gene-specific identification techniques relying on methylation-specific PCR (MSP) require a lengthy manual benchtop process that is susceptible to human-error and contamination. This MSP assay requires a series of discrete sample processing steps including genomic DNA extraction, bisulfite conversion and readout via PCR. In this work, we present a streamlined assay platform utilizing droplet magnetofluidic principles for integration of all sample processing steps required to obtain quantitative MSP signal from raw biological samples. We present a streamlined protocol for solid-phase extraction and bisulfite conversion of genomic DNA, which minimizes reagent use and simplifies the sample preparation protocol for implementation on a compact assay platform. Furthermore, we present a thermally robust assay chip that enables DNA extraction, bisulfite conversion and quantitative PCR from biological samples on a single device. Technical improvements to facilitate DNA extraction and PCR on a single chip in addition to chip performance characterization data are presented.
KeywordsMethylation Epigenetics Methylation-specific PCR Lab-on-chip Magnetofluidics qPCR Biomarkers
The authors would also like to thank funding sources from National Institutes of Health (R21CA186809, UG3CA211457, U01CA200499).
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