Pressure-driven one-step solid phase-based on-chip sample preparation on a microfabricated plastic device and integration with flow-through polymerase chain reaction (PCR)

• Solid phase-based extraction and purification of DNA was performed on chip.
• Plastic microdevice was fabricated using poly(methylmethacrylate) (PMMA).
• Working principle of Chelex cation exchange resin for DNA preparation was suggested.
• Chelex was applied as a solid support for genomic DNA preparation from human hairs.
• Integration of on-chip DNA preparation and amplification units were investigated.

In this study, we fabricate a monolithic poly(methylmethacrylate) (PMMA) microdevice on which solid phase-based DNA preparation and flow-through polymerase chain reaction (PCR) units were functionally integrated for one-step sample preparation and amplification operated by pressure. Chelex resin, which is used as a solid support for DNA preparation, can capture denatured proteins but releases DNA, and the purified DNA can then be used as a template in a subsequent amplification process. Using the PMMA microdevices, DNA was successfully purified from both Escherichia coli and human hair sample, and the plasmid vector inserted in E. coli and the D1S80 locus in human genomic DNA were successfully amplified from on-chip purified E. coli and human hair samples. Furthermore, the integration potential of the proposed sample preparation and flow-through PCR units was successfully demonstrate on a monolithic PMMA microdevice with a seamless flow, which could pave the way for a pressure-driven, simple one-step sample preparation and amplification with greatly decreased manufacture cost and enhanced device disposability.