Strategically Designing a Pumpless Microfluidic Device on an "Inert" Polypropylene Substrate with Potential Application in Biosensing and Diagnostics

Langmuir. 2017 Jun 6;33(22):5565-5576. doi: 10.1021/acs.langmuir.7b00537. Epub 2017 May 22.

Abstract

This study is an attempt to make a step forward to implement the very immature concept of pumpless transportation of liquid into a real miniaturized device or lab-on-chip (LOC) on a plastic substrate. "Inert" plastic materials such as polypropylene (PP) are used in a variety of biomedical applications but their surface engineering is very challenging. Here, it was demonstrated that with a facile innovative wettability patterning route using fluorosilanized UV-independent TiO2 nanoparticle coating it is possible to create wedge-shaped open microfluidic tracks on inert solid surfaces for low-cost biomedical devices (lab-on-plastic). For the future miniaturization and integration of the tracks into a device, a variety of characterization techniques were used to not only systematically study the surface patterning chemistry and topography but also to have a clear knowledge of its biological interactions and performance. The effect of such surface architecture on the biological performance was studied in terms of static/dynamic protein (bovine serum albumin) adsorption, bacterial (Staphylococcus aureus and Staphylococcus epidermidis) adhesion, cell viability (using HeLa and MCF-7 cancer cell lines as well as noncancerous human fibroblast cells), and cell patterning (Murine embryonic fibroblasts). Strategies are discussed for incorporating such a confined track into a diagnostic device in which its sensing portion is based on protein, microorganism, or cells. Finally, for the proof-of-principle of biosensing application, the well-known high-affinity molecular couple of BSA-antiBSA as a biological model was employed.

MeSH terms

  • Animals
  • Biosensing Techniques
  • Humans
  • Lab-On-A-Chip Devices
  • Mice
  • Microfluidics*
  • Polypropylenes
  • Staphylococcus epidermidis
  • Wettability

Substances

  • Polypropylenes