亞麻仁油酸及共軛亞麻仁油酸改質聚胺酯的合成鑑定與血液相容性探討

Synthesis, Characterization and Hemocompatibility Study of Linoleic-acid- and Conjugated-octadecadienoic-acid-modified Polyurethanes

林曉淇(Hsiao-Chi Lin)

指導教授 ： 王賢達

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2007年)

摘要

聚胺酯（Polyurethane）現今已廣泛應用於生醫材料中，因其具有硬、軟節段各自聚集的現象，形成微相分離(Microphase Separation) 。除了可以提供良好的機械性質，因微相分離的結構與天然組織類似，故不易引起血小板黏附、集聚，具有生物相容性。且其硬質段中因含有NH-COO鍵結與細胞胺基酸組成相似，可以提供與體內較類似的環境，因此具有較好的生物相容性。常運用在人工心臟、人工血管和導管等。
本實驗是利用具有抗凝血性質的C18不飽和脂肪酸—亞麻仁油酸(LA)和共軛亞麻仁油酸(CLA)，與分子量為1000與650的聚醇 (PTMO)反應，經酯化72小時，純化後以預聚合法成改質PU，為了縮短酯化時間，加入對甲苯磺酸(p-TSA)當催化劑，可將酯化時間從72小時縮短至4小時；而後利用1H NMR定量LA的酯化反應率，最高可達99%；1H 與13C NMR鑑定其結構，光譜顯示出預聚物(Prepolymer)的特徵峰；FTIR顯示微相分離程度，依LA酯化率增加而增加，並依PTMO分子量的減少而增加；GPC呈現單分布，隨著LA酯化量的增加，改質聚胺酯的分子量有逐漸變小的趨勢。LA及CLA酯化量越高，都有助於延長凝血時間。在蛋白質吸附測定，發現當LA及CLA酯化量越高，白蛋白的吸附越優於纖維蛋白原；而血小板黏附實驗中，改質PU利用SEM觀測吸附血小板形態時，也較不易活化變形，尤以CLA改質PU為最。

關鍵字

聚胺酯 ； 改質聚胺酯 ； 亞麻仁油酸 ； 共軛亞麻仁油酸 ； 蛋白質吸附 ； 血小板黏附

並列摘要

During the past few decades, polyurethanes (PUs) have been widely used for biomedical applications due to their excellent mechanical properties and comparatively good tissue and blood compatibility. It has been reported that polyurethane with an C18 alkyl side chain, grafting from the polyurethane backbone shows a high affinity for albumin adsorption and low platelet reactivity.
In my study, linoleic acid (LA) or conjugated linoleic acid (CLA) has been esterified with poly(tetramethylene oxide)(PTMO), and this prepolymer, 4,4’-diphenylmethane diisocyanate and 1,4-butane diol were synthesized into PU.. In order to shorten esterification time, toluene sulfonic acid (p-TSA) were used as the catalyst.The reaction time has been effectively shortened from 72 hours to 4 hours. 1H NMR was used to determine the efficiency of LA and CLA incorporation to the chain end of PU. 13C NMR was also used to characterize modified PU chain structure. FT-IR spectra displayed more microphase separation for modified PU with lower PTMO molecular weight (650).
Adsorption of human serum albumin (HSA) or human serum fibrinogen (HPF) for LA or CLA-grafted PU indicated higher HSA/APF ratio. The modified PUs displayed longer blood coagulation time, platelets adsorbed also exhibited a relatively passive morphology.

並列關鍵字

Polyurethane ； Linoleic Acid ； Conjugated Linoleic Acid ； Blood Coagulation ； Protein Adsorption ； Modified Polyurethane

參考文獻

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