A study on the adsorption of endotoxin on polymyxin B and polyethylene glycol immobilized surfaces

• Main Authors: Jyun-Ying Chen, 陳俊穎
• Other Authors: Ruey-Yug Tsay
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/96727854015265355673

碩士 === 國立陽明大學 === 醫學工程研究所 === 99 === The detection and removal of endotoxin (LPS) molecules are important issues in the development of implanted biomedical devices. This research study the effects of PEG chain density, which is manipulated by changing the molecular weight of PEG, adsorption order, and solvent,and the immobilization of PMB molecules on the specific and nonspecific adsorptions of LPS molecules. We also use Poly-L-lysine to adsorb LPS, and conjugate PMB on Poly-L-lysine to increase the adsorption of LPS. Qualitative analysis of Au adsorbed films is carried out by FTIR. The film thickness and surface concentration are measured by ellipsometry and SPR, respectively. The film of HS-PEG is not stable on gold. It takes long time to reach a stable film thickness for a desorption test. The film thickness of the adsorbed HS-PEG2000-COOH (Mw = 2000 dalton) film is the highest, and the film thickness of HS-PEG1000-COOH film is the lowest. The thickness of a mixed-PEG film is between HS-PEG2000 and HS-PEG1000. We use alcohol of C2-C8 as the solvent of NH2-PEG, and the film thickness of NH2-PEG-COOH increases with the carbon chain length of alcohol. The nonspecific adsorptions of PMB and LPS on PEG films are trivial. The PMB nonspecific adsorption and PEG film thickness are negative correlation. The amount of PMB immobilized on HS-PEG is limited. The film thickness of PMB conjugated on NH2-PEG is about 0.5 nm, which doesn’t change with PEG film thickness. PMB conjugated on PEG adsorbs little LPS. This is probably because PMB is embedded in the NH2-PEG film. Poly-L-lysine (PLL) exhibit LPS adsorption ability and by conjugating PMB on Poly-L-lysine can increase the LPS adsorption. The LPS specific adsorptions between PMB-PLL and PMB-SAM are about the same.