A size reduction method for rapid digital PCR using thin-film chip and vacuum pouch microfluidic system
Journal
Microfluidics and Nanofluidics
Journal Volume
26
Journal Issue
1
Date Issued
2022
Author(s)
Abstract
The digital polymerase chain reaction (dPCR) is a high efficacy detection method that is widely applied in lab-on-a-chip systems. Reported dPCR microfluidic devices usually require a high level of system integration, including a fluidic manipulating system, a thermal cycling system, an optical system, and a power source. To effectively reduce system size and complexity, we integrate thin-film dPCR chip and the vacuum pouch microfluidic (VPM) system to eliminate the fluidic manipulation system and to reduce energy demand on the thermal cycler. The VPM system integrates fluidic handling system on-chip by using a vacuum seal bag to enclose the thin-film dPCR chip and to store negative pressure. This design makes operation simple: load PCR mix and oil on the pouch surface then pierce the film surface to initiate loading and droplet generation. The thin-film dPCR chip is a 0.288?mm-thick cyclo-olefin-polymer film embedded with a passive droplet generator, and the distance from droplets to the chip surface is less than 50?μm. This design makes this chip have a low thermal mass and a short thermal conducting length, and the demand on the heating and cooling power of the thermal cycler can be largely reduced. A polyimide thermofoil heater and a small cooling fan are sufficient to complete 35 amplification cycles in 4.84?min. Combining these two technologies, this VPM–dPCR system is lightweight, compact, and conserves energy, and the dPCR chip is disposable. Finally, its capability to perform dual-target detection also is demonstrated by quantifying two microRNA targets in one VPM–dPCR chip. ? 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Subjects
Digital PCR
Point-of-care testing
Self-digitization
Self-driven microfluidics
Thin-film microfluidic chip
Vacuum pouch microfluidic system
Chip scale packages
Digital microfluidics
Drops
Fluidic devices
Optical systems
Polymer films
Programmable logic controllers
RNA
System-on-chip
Thin films
Digitisation
Microfluidic-chips
Microfluidics systems
Self-driven
Self-driven microfluidic
Thin-films
Polymerase chain reaction
Type
journal article