접촉각 조절 가능 Bio-functional 플라스틱 플루이딕 칩의 제작에 대한 연구

Abstract

Recently, the research of replacing a glass substrate with a plastic substrate is being much progressed due to the advantages that the price is cheap and formation of structures is easy in manufacturing the fluidic chips. Although the plastic substrate has more advantages than the glass substrate, there is a problem in the flow of fluid since the substrate surface is hydrophobic. There are methods available such as chemical treatment, ultraviolet irradiation and O2 plasma treatment to modify the existing plastic substrate to have a hydrophilic property. The chemical treatment method has a limit in application for mass production due to process sensitivity and waste. Also the hydrophilic property is not permanent when the ultraviolet irradiation and O2 plasma treatment methods are applied. This largely hampers the reliability of plastic fluidic chips and acts as a big problem for commercialization. The new method of hydrophilic surface treatment is required to overcome these problems. In order to overcome the problems of hydrophilic surface treatment methods of the existing plastic substrate, this study investigated the deposition of SiO2 thin film on plastic substrates by sputtering and they are modified with amine by using a Liquid Self-Assembled Monolayer (L-SAM) method. It was able to obtain smooth flow of fluid on a plastic channel with the easy immobilization of protein and DNA in the formed amine surface. All substrates including a plastic substrate can be modified to a hydrophilic surface to obtain excellent bio-stability and functional groups such as aldehyde and carboxylic acid, etc. In order to assess the modified hydrophilic surface, the permanent hydrophilic property and bio compatibility were investigated by using the contact angle and fluorescent measurements. Also XPS (X-ray Photoelectron Spectroscopy) analysis was carried out to measure an amine formation level by L-SAM (liquid-Self Assembly Monolayer) treatment.