3D printed microfluidic chip design for diagnostic studies

¹ Department of Human Biology, University of Cape Town, South Africa.
² Biophotonics, Council for Scientific and Industrial Research, South Africa.
³ College of Graduate Studies, University of South Africa, South Africa.

Abstract

In this study, additive manufacturing (3D printing) is utilised to fabricate lateral flow microfluidic chips (LFMC). Our chips were designed using Autodesk design software and printed using a Formlabs 3D printer. They are printed using Formlabs V4 resin polymer. In this work, the design process is highlighted in detail and shows an LFMC design that is made for potential applications in diagnostics studies. Our study also tested the performance of one of the chip designs in actual diagnostics experiment on an optical transmittance setup with a peristaltic pump. The LFMC was integrated onto a custom-built transmittance optical biosensor to measure the transmission intensity. A real-time kinetic study was conducted using an HIV-1 oligonucleotide probe. The study involved performing real-time transmittance analysis by pumping the HIV-1 oligonucleotide probe at different flow rates, ranging from 9. 5 μm/min to 13 μm/min with intervals of 0.5 μm/min. During the experiment, transmission intensity or transmitted light was measured in real time as the oligonucleotide HIV probe bound to neutravidin immobilised on the Au metal surface. These measurements were recorded using a USB400 spectrometer, with a broad- band UV light source that emits wavelengths ranging from 400 to 800 nm. The study underscored the significance of microfluidic chips as devices capable of enhancing the performance of biosensors as well as the use of 3D printing in the design and manufacture of these microfluidic chips.