調控類雙離子水凝膠之血液相容性質

Hemocompatible control of pseudozwitterionic hydrogels

徐可人(Ko-Jen Hsu)

指導教授 ： 張雍

中原大學/工學院/化學工程研究所/碩士(2015年)

https://doi.org/10.6840/cycu201500452

摘要

本研究成功製備類雙離子型水凝膠，並系統性的探討該類型水凝膠界面之血液相容性質。研究系統以帶有隱性正電單體(一級氨基[Acrylamide]與二級氨基N-isopropylacrylamide [NIPAAm])和顯性正電單體(三級氨基(Dimethylamino)ethyl methacrylate [DMAEMA]與四級氨基[2(Methacryloyloxy)ethyl]trimethylammonium chloride [TMA])分別混合顯性負電荷性單體3-Sulfopropylmethacrylate potassium salt (SA)，以化學鍵結方式交聯聚合出具不同電荷偏差之類雙離子性水凝膠，並探討其與人體血液中的血漿蛋白與人體血球之相互作用情形。
將不同電荷偏差之類雙離子性水凝膠，透過表面接觸角量測儀、表面含水率、化學分析電子光譜儀、傅里葉紅外線光譜儀、與粒子電位雷射量測儀等方式檢測水凝膠的親水性、化學組成與結構、與電荷偏差程度。研究中，使用酵素免疫吸附法測試人體內蛋白質於水凝膠表面的吸附行為，並由雷射共軛焦顯微鏡觀察人體內血小板及人體血球於水凝膠表面的貼附情形，研究發現不同電荷偏差之類雙離子水凝膠，表面展現相同之親水特性，帶有顯性正電單體DMAEMA、TMA與負電單體SA混合之水凝膠，可藉由不同混合比例去調控電荷偏差程度，在與血漿蛋白、紅血球、白血球、血小板接觸，當水凝膠之莫爾比例為SA/DMAEMA ~ 30/70與SA/TMA ~50/50時，水凝膠界面能有效抗生物沾黏，而帶有隱性正電荷單體Acrylamide、NIPAAm結構主要是以醯胺鍵為主，所以無法在待測溶液中產生正電荷，固其與SA交聯成水凝膠，其整體電荷主要是由SA所主導。最後將血球與水凝膠界面電荷進行關聯性分析，發現當表面電位藉於10 mV ~ -10 mV，能有效降低血小板、紅血球以及白血球之貼附，而超過這個電荷區間，血液細胞又會開始沾黏在材料表面，找到一個抗血球貼附之電荷區間，未來可藉由調整電荷控制血球沾黏程度，廣泛應用在生醫方面。

關鍵字

類雙離子 ； 水凝膠 ； 血液相容性 ； 電荷偏差

並列摘要

The aim of this study is the preparation of pseudozwitterionic hydrogels with negatively and positively charged monomers in different ratios and the discussion of its hemocompatibility. The positively charged monomers of Acrylamide, N-isopropylacrylamide (NIPAAm), (Dimethylamino)ethyl methacrylate (DMAEMA), and [2(Methacryloyloxy)ethyl]trimethylammonium chloride (TMA) are used to separately mix with the negatively charged monomer of 3-Sulfopropylmethacrylate potassium salt (SA). These monomers in different ratios were introduced to prepare the pseudozwitterionic hydrogels by thermal-induced cross-linking reaction. The interaction between the hydrogel surface and human blood components (proteins and cells) was also analyzed.
The hydrophilicity, zeta potential, and composition of the prepared pseudozwitterionic hydrogels were characterized by contact angle (CA), laser doppler electrophoresis (LDE), X-ray photoelectron spectroscopy (XPS), and Fourier Transform Infrared Spectrometer (FTIR), respectively. Blood compatibility of the prepared hydrogels was evaluated by the tests of platelet adhesion and blood cell attachment. In addition, the images of blood cell attachment were observed by laser scanning confocal microscope (LSCM) and scanning electron microscope (SEM). Plasma protein adsorption was determined by an enzyme-linked immune sorbent assay (ELISA).
The results showed that the hydrophilicity of the prepared pseudozwitterionic hydrogels was controlled in the same range. The tertiary and quaternary amine groups in the prepared SA/DMAEMA and SA/TMA hydrogels contribute the resulting interfaces with positive zeta potential. However, the recessive positively charged monomer acrylamide and NIPAAm has amide groups. It is difficult to release the positive charge for an amide structure compared to the amine structure in the tested solution. LSCM and SEM images showed that the surfaces adhered only a few amount of erythrocytes, leukocytes and platelets when the ratio of SA/DMAEMA close to 30/70 and SA/TMA close to 50/50.
As a result, the overall charge-bias level of hydrogel is mainly dominated by the content of SA in the prepared samples. Thus, the blood cell attachment is related to the zeta potential of the corresponding interfaces. It was found that the optimized surface zeta potential to inhibit blood cell adhesion is at 10mV ~ -10 mV, It can effectively reduce the platelets, erythrocyte and leukocyte attachment. When surface charge is out of this range, the blood cells intended to attach on the surfaces. It was found that the blood cell attachment was controlled by the ratios of positively and negatively charge segments, which provided the molecular design principle for the blood cell selections.

並列關鍵字

pseudozwitterionic ； hydrogel ； hemocompatibility ； charge-bias

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