Sensitive, Rapid, and Automated Detection of DNA Methylation Based on Digital Microfluidics

Abstract

Biomarkers based on DNA methylation have attracted wide attention in biomedical research due to their potential clinical value. Therefore, a sensitive and accurate method for DNA methylation detection is highly desirable for the discovery and diagnostics of human diseases, especially cancers. Here, an integrated, low-cost, and portable point-of-care (POC) device is presented to analyze DNA methylation, which integrates the process of pyrosequencing in a digital microfluidic chip. Without additional equipment and complicated operation, droplets are manipulated by patterned electrodes with individually programmed control. The system exhibited an excellent sensitivity with a limit of detection (LOD) of 10 pg and a comparable checkout down to 5% methylation level within 30 min, which offered a potential substitute for the detection of DNA methylation. With the advantages of portability, ease of use, high accuracy, and low cost, the POC platform shows great potential for the analysis of tumor-specific circulating DNA.

Advances in integrated digital microfluidic platforms for point-of-care diagnosis: a review

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Integrated Microfluidic-Based Platforms for On-Site Detection and Quantification of Infectious Pathogens: Towards On-Site Medical Translation of SARS-CoV-2 Diagnostic Platforms

“…Through automation, the need for manual operation, technically trained operators, constant reagent supply and expensive equipment is heavily mitigated. Ruan et al demonstrated the effectiveness of automation through a fully automated electrode-controlled procedure to dispense uniform phosphate-buffered saline droplets for the detection of DNA methylation [ 48 ]. Thus, the variance that might have resulted from human error was effectively removed and the reliability and reproducibility of this assay were increased.…”

Cilo-seq: highly sensitive cell-in-library-out single-cell transcriptome sequencing with digital microfluidics

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