Droplet bisulfite conversion platform for epigenetic cancer biomarker detection

We report an integrated digital microfluidic platform for methylation biological samples. Recent advances in epigenetic studies highlight the importance of DNA methylation in the biology of cancer. The epigenetic signature of promoter regions in the genes ADAMTS1 and BNC1 has been shown to have strong correlation with the early stages of pancreatic carcinogenesis [1]. Most analytical techniques for studying methylation require pre-processing of sample DNA via bisulfite conversion. However, repetitive addition and removal of liquid reagents using conventional tubes and pipettes present a technical hurdle for microliter-scale reagents, as well as a high risk for contamination and human error. Previously, we reported a magnetically actuated platform for integrated DNA extraction and amplification from crude biological samples [2]. In this work, we demonstrate a self-contained, magnetically-actuated droplet cartridge for bisulfite treatment of genomic DNA with enhanced performance compared to the tube-based process.