The Effects of the Immobilization of Polymyxin B

• Main Authors: Cheng-Ping Liu, 劉正平
• Other Authors: Ruey-Yug Tsay
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/65605123625861858793

碩士 === 國立陽明大學 === 醫學工程研究所 === 95 === In this research, mixed SAM of HS-(CH2)15-CH3 and HS-(CH2)15-COOH was immobilized on gold substrate through chemical bond, and PEG and PMB were in sequence linked to the –COOH terminal groups on the SAM sureface by EDC/NHS amide coupling. The PMB immobilized surface was applied to study its specific and nonspecific interactions with LPS by ellipsometry and by SPR spectroscopy. The modified surface is characterized by FTIR, XPS, ellipsometry and contact angle measurements. The results indicated that the contact angle of a -CH3/-COOH terminated mixed monolayer with more than 70% of –COOH changes slightly after long term storage in N2 atomosphere. The nonspecific adsorption of PMB and LPS on a PEG-grafted mixed monolayer shows a bell-shaped distribution with the fraction of the –COOH on the SAM surfaces, ie. the adsorptions are lower for SAM with pure -CH3 or –COOH terminal groups. From the adsorption isotherm, one obtains the equilibrium adsorption constant of LPS at 37˚C on a PMB-modified SAM surface which is immobilized at pH=8.41 of 3.63 * 10^7 M-1. Also, from the dynamic adsorption curve, one obtains a value of 3.26*10^3 M-1s-1 for the adsorption rate constant of LPS-PMB interaction.