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Environmentally responsive materials based on block-, graft-, and cross-linked copolymers for pharmaceutical applications.

機譯：基于嵌段共聚物，接枝共聚物和交聯(lián)共聚物的環(huán)保材料，用于制藥應(yīng)用。

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摘要

Polymer materials have been developed for various biomedical applications. This thesis document attempts to develop and characterize novel classes of environmentally responsive polymer complex materials for drug delivery. These materials are based on block-, graft-, and cross-linked copolymers that contain the following major elements of different functionality: (1) hydrophilic ("water-soluble") polymer block, polyethylene oxide (PEO); (2) hydrophobic ("water-insoluble") block, polypropylene oxide (PPO); (3) anionic polyelectrolyte block, polyacrylic acid (PAA). The hydrophilic PEO block facilitates dispersion or swelling of the materials in an aqueous environment. The hydrophobic PPO block exhibits temperature dependent hydration/dehydration behavior that was employed to prepare the temperature responsive materials. The polyelectrolyte PAA block can bind oppositely charged molecules such as salts, surfactants, and proteins and serves as a structural domain that is responsive to changes in pH and ionic strength.;Three basic types of materials were studied: (1) blends of PEO-PPO-PEO block copolymers (PluronicRTM) of different block length, (2) complexes of PAA grafted with PluronicRTM (Pluronic-PAA) and cationic surfactants, (3) cross-linked networks of PEO and PAA (PEO- cl-PAA) with proteins. First, mixtures of hydrophilic and hydrophobic PluronicRTM displayed a temperature dependent self assembly behavior, forming micellar aggregates of different structures. The aggregates were characterized with small size (100 nm to 250 nm), high stability in dispersion, and greater solubilization capacity with respect to hydrophobic compounds compared to micelles formed by one type of PluronicRTM. Second, stable dispersed block ionomer complexes (BIC) were formed by mixing Pluronic-PAA and cationic surfactants. These complexes exhibited a thermotropic and pH sensitive behaviors, displayed high solubilization capacity with respect to hydrophobic drugs that incorporated into domains formed by surfactant tails bound to the PAA chains. Third, the polyelectrolyte networks of PEO- cl-PAA showed the pH and salt dependent swelling, and displayed high capacity for sorption of a protein, cytochrome C, due to formation of electrostatic complex between polyelectrolyte and protein. By adding Ca2+, the protein was released from the complex in the external medium. Overall this study developed three new classes of functional nanoscale materials for future applications in the controlled drug release and delivery systems.
機譯：聚合物材料已經(jīng)被開發(fā)用于各種生物醫(yī)學(xué)應(yīng)用。本論文試圖開發(fā)和表征用于藥物遞送的新型類別的對環(huán)境敏感的聚合物復(fù)合材料。這些材料基于嵌段共聚物，接枝共聚物和交聯(lián)共聚物，它們包含以下不同功能的主要元素：（1）親水性（“水溶性”）聚合物嵌段，聚環(huán)氧乙烷（PEO）； （2）疏水性（“水不溶性”）嵌段，聚環(huán)氧丙烷（PPO）； （3）陰離子聚電解質(zhì)嵌段，聚丙烯酸（PAA）。親水性PEO嵌段促進材料在水性環(huán)境中的分散或溶脹。疏水性PPO嵌段具有隨溫度變化的水合/脫水行為，可用于制備溫度響應(yīng)性材料。聚電解質(zhì)PAA嵌段可以結(jié)合帶相反電荷的分子（例如鹽，表面活性劑和蛋白質(zhì)），并作為對pH和離子強度變化做出響應(yīng)的結(jié)構(gòu)域。；研究了三種基本類型的材料：（1）PEO-的共混物不同嵌段長度的PPO-PEO嵌段共聚物（PluronicRTM），（2）用PluronicRTM（Pluronic-PAA）和陽離子表面活性劑接枝的PAA配合物，（3）PEO和PAA的交聯(lián)網(wǎng)絡(luò)（PEO-cl-PAA）與蛋白質(zhì)。首先，親水性和疏水性PluronicRTM的混合物表現(xiàn)出溫度依賴性的自組裝行為，形成不同結(jié)構(gòu)的膠束聚集體。與由一種類型的PluronicRTM形成的膠束相比，這些聚集體的特征是尺寸小（100 nm至250 nm），分散穩(wěn)定性高以及對疏水化合物的增溶能力。第二，通過混合Pluronic-PAA和陽離子表面活性劑形成穩(wěn)定的分散嵌段離聚物復(fù)合物（BIC）。這些復(fù)合物表現(xiàn)出熱致和pH敏感的行為，相對于疏水性藥物表現(xiàn)出高增溶能力，該疏水性藥物摻入由與PAA鏈結(jié)合的表面活性劑尾部形成的域中。第三，由于聚電解質(zhì)和蛋白質(zhì)之間形成靜電復(fù)合物，所以PEOcl-PAA的聚電解質(zhì)網(wǎng)絡(luò)顯示出pH和鹽依賴性溶脹，并顯示出高的蛋白質(zhì)吸附能力，即細(xì)胞色素C。通過添加Ca2 +，蛋白質(zhì)從復(fù)合物在外部介質(zhì)中釋放出來?？傮w而言，本研究開發(fā)了三類新的功能納米級材料，以供將來在受控藥物釋放和遞送系統(tǒng)中應(yīng)用。

著錄項

  • 作者

    Oh, Kyung T.;

  • 作者單位

    University of Nebraska Medical Center.;

  • 授予單位 University of Nebraska Medical Center.;
  • 學(xué)科 Chemistry Pharmaceutical.;Health Sciences Pharmacy.
  • 學(xué)位 Ph.D.
  • 年度 2006
  • 頁碼 202 p.
  • 總頁數(shù) 202
  • 原文格式 PDF
  • 正文語種 eng
  • 中圖分類 藥物化學(xué);藥劑學(xué);
  • 關(guān)鍵詞

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