Abstract
Control of surface properties is very important in high performance microfluidic devices because appropriate functionalization of the surface of the microchannel helps to minimize adsorption of certain analytes thus improving its performance. In this regard, both the argon and oxygen plasma techniques have been used to improve the adaption of polymer surfaces to biological environments. However, the less common nitrogen plasma technique has not been used for surface modification of cyclic olefin copolymer (COC) in microfluidic applications. This paper presents a comparative study between the argon, oxygen, and nitrogen plasma treatments with the aim to identify the most suitable process for the development of a smart, disposable chip for the Bio-MEMS application. The chemical and morphological changes of the plasma modified COC surfaces were characterized using X-ray photoelectron spectroscopy, atomic force microscopy, and water contact angle measurements. The effect of plasma treatment on the strength of thermally bonded lap-shear specimens was studied. The influence of plasma treatment on the integrity of thermally sealed microdevices was assessed using burst pressure tests. The plasma treatments had a significant impact on the electroosmosis flow mobility in the microchannels. The hemocompatibility of the various plasma-modified COC surfaces was determined using the static platelets adhesion experiment. It was shown that the nitrogen plasma treatment was more effective than the argon and oxygen treatments for the modification of COC based microfluidic devices. A schematic picture of a microfluidic device for micro-mixing that was successfully sealed by thermal bonding after nitrogen plasma treatment. The scanning electron micrograph on the right shows a magnified view of two channels in the microdevice showing good shape and dimensional integrity of the microchannels after thermal bonding at 125°C with a bonding pressure of 2MPa and a bonding time of 6min. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
| Original language | English |
|---|---|
| Pages (from-to) | 432-443 |
| Journal | Plasma Processes and Polymers |
| Volume | 8 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - 20 May 2011 |
| Externally published | Yes |
Bibliographical note
Publication details (e.g. title, author(s), publication statuses and dates) are captured on an “AS IS” and “AS AVAILABLE” basis at the time of record harvesting from the data source. Suggestions for further amendments or supplementary information can be sent to [email protected].Research Keywords
- adhesion
- COC
- microfluidics
- molding
- plasma treatment
- platelet adhesion
- thermal bonding
- wettability
- XPS