Microfluidic chip fabrication and performance analysis of 3D printed material for use in microfluidic nucleic acid amplification applications

Charalampos Tzivelekis,Hojjat Madadi,Kenny Dalgarno,Matthew P Selby,Albert Batet

doi:10.1088/1361-6439/abd9a9

Abstract

Additive manufacturing for microfluidics shows potential to boost research and development in research biology and molecular diagnostics. This paper reports on novel process and material optimisation techniques in the creation of a monolithic microfluidic chip geometry for polymerase chain reaction (PCR) thermocycling using stereolithography (SLA). A two-stage printing protocol with projection SLA is assessed in printing disposable oscillating-flow microfluidic cartridges for PCR. Print performance was characterized in terms of critical channel dimensions and surface quality. Post-treatment with ultraviolet light and solvent washes was shown to reduce PCR inhibiting residuals and facilitate the reaction, indicating material compatibility for fluidic and milli-fluidic PCR architectures. Residuals leaching from the polymer were shown via quantitative PCR that interact with enzyme activity. Passivation of channel surfaces with a polyethylene glycol and a silane static coating reduced the leaching interface improving overall PCR efficiency. The discussed protocols can serve as a low-cost alternative to clean-room and micromachined microfluidic prototypes for various microfluidic concepts.

Highlights

Miniaturization of nucleic acid amplification on a microfluidic device was introduced in the early 90s [1, 2]
This paper reports on novel process and material optimisation techniques in the creation of a monolithic microfluidic chip geometry for polymerase chain reaction (PCR) thermocycling using stereolithography (SLA)
A full two-step PCR protocol ran with 80:20 water:glycerol with no leakages observed at the functional temperatures

Summary

Introduction

Miniaturization of nucleic acid amplification on a microfluidic device was introduced in the early 90s [1, 2]. This was due to the multiple benefits in terms of reagents costs, performance. Numerous studies reported on complete nucleic acid testing systems, with some of them translated into commercial applications [4]. These lab-on-chip platforms incorporate microfluidic technology and microelectromechanical system components to perform complex, highthroughput operations with fluid samples, and have displayed outstanding performance compared to traditional lab-methods.

Methods

Results

Discussion

Conclusion