本研究使用聚乙二醇與左旋-丙交酯以開環聚合法合成聚乳酸-聚乙二醇-聚乳酸(poly(L-lactide)-poly(ethylene glycol)-poly(L-lactide))(PLLA-PEG-PLLA)三團聯共聚物。將共聚物的親水鏈段PEG聚合度固定為91，再利用凝膠滲透層析儀(GPC)對共聚物進行分子量的分析，計算出疏水段PLLA聚合度為74、103和132。
以螢光探針法測量共聚物水溶液之臨界微胞濃度，可以觀察到疏水鏈段聚合度越大時，其臨界微胞濃度越小，越易形成微胞。將三團聯共聚物和不同粒徑之氧化鋅奈米粒子利用共沉澱法於水溶液中共組裝後，發現其臨界微胞濃度減少，代表氧化鋅奈米粒子和共聚物共組裝形成微胞時，奈米粒子增加了微胞的熱力學親和力，使微胞之疏水性增加，而隨著所包覆奈米粒子粒徑減少，其增加疏水性的效果更為明顯。再由共聚物水溶液之臨界微胞濃度計算微胞化自由能，發現當疏水鏈段長度越大時，其微胞化自由能之絕對值越大，代表疏水鏈段長度增加時，其微胞化之驅動力較大，較易形成微胞。而加入氧化鋅奈米粒子則能增加微胞化之驅動力，使微胞更易形成，且所包覆奈米粒子粒徑越小，此效果越明顯。
以動態光散射儀測量微胞在水溶液中之平均粒徑，發現共聚物的疏水鏈段聚合度越大時，測得微胞在水溶液中的平均粒徑也越大，而包覆之氧化鋅奈米粒子粒徑越大時，微胞平均粒徑也越大。由於氧化鋅奈米粒子結構存在缺陷而帶正電，所以兩奈米粒子間有斥力產生，而奈米粒子粒徑越大，粒子間的斥力越大，導致微胞平均粒徑上升。
利用熱重量分析徑儀測量氧化鋅奈米粒子在微胞疏水核中之重量百分率，探討奈米粒子粒對包覆平衡常數、分配自由能之影響。
實驗結果發現當所包覆之氧化鋅奈米粒子和PLLA-PEG-PLLA三團聯共聚物共組裝時，隨著微胞包覆之奈米粒子粒徑越大，平衡常數、分配自由能(負值)之絕對值變大，即所包覆奈米粒子粒徑越大，奈米粒子從水溶液中進入微胞疏水核中之驅動力越大。
為探討微胞包覆奈米粒子和藥物之包覆平衡常數和分配自由能的關係，本實驗以紫外/可見光分光光度計測定Vitamin K3於殘液之吸光光譜，利用檢量線得到未包覆藥物時的殘液濃度，計算藥物包覆平衡常數和分配自由能，實驗結果發現Vitamin K3之平衡常數、分配自由能(負值)之絕對值皆較氧化鋅奈米粒子小。
研究發現微胞粒徑和奈米粒子粒徑皆會對共聚物水溶液之臨界微胞濃度、微胞在水溶液中之平均粒徑、平衡常數、分配自由能造成影響，而其中微胞粒徑所造成之影響較明顯。

In this experiment, polyethylene glycol and L-lactide are used to synthesize poly(L-lactide)-poly(ethylene glycol)-poly(L-lactide) by ring-opening polymerization. The degree of polymerizations of the hydrophilic segment PEG in the copolymers are controlled to 91. The molecular weights of the copolymers are measured by gel permeation chromatography (GPC) and the degrees of polymerizations of the hydrophobic segment PLLA are calculated to be 74, 103 and 132.
The critical micelle concentrations of the copolymers in aqueous solutions are measured by fluorescent probe method. It can be observed that the greater the degree of polymerization of the hydrophobic segment, the smaller the critical micelle concentration and the easier the formation of micelles. We co-assemble triblock copolymers and different sizes of zinc oxide nanoparticles in aqueous solutions by co-precipitation method. It is found that the critical micelle concentration decrease with the addition of particles. It means that when zinc oxide nanoparticles and copolymers are co-assembled to form micelles, the nanoparticles increase the thermodynamic affinity between micelle cores and water. As the sizes of the nanoparticles incorporated within micelles decrease, the effect of increasing the hydrophobicity becomes more obvious.
The average sizes of the micelles in the aqueous solutions are measured by dynamic light scattering. It is found that the larger the degrees of polymerization of the hydrophobic segments, the larger the average sizes of the micelles. And the larger the particle sizes of zinc oxide nanoparticles incorporated within micelles, the larger the average sizes of the micelles. Because zinc oxide nanoparticle has defects in its structure, it is positively charged. There are the repulsive forces between two nanoparticles. The larger the sizes of the nanoparticles, the greater the repulsive forces between the particles, resulting in an increase in sizes of the micelles.
The weight percentages of zinc oxide nanoparticles in the hydrophobic core of the micelles are measured by thermogravimetric analysis, and we explore the influence of the nanoparticle size on the particle loading equilibrium constant and the free energy of partition. The experimental results show that when zinc oxide nanoparticles and PLLA-PEG-PLLA tripolymer are co-assembled,and the sizes of the nanoparticles incorporated within micelles increases, the equilibrium constants and the absolute free energy of partition becomes larger. That is, the larger the sizes of the nanoparticles, the greater the driving force for the nanoparticles to enter the hydrophobic cores of the micelles.
In order to explore the relationship between the loading equilibrium constants and the free energy of partition of the micelle loaded with nanoparticles and drug. The absorption spectrums of Vitamin K3 in the residual liquid are measured by UV/visible spectroscopy. Using the calibration curve to obtain the concentrations of the loaded drug. The loading equilibrium constant and the free energy of partition of drug can be calculated. The experimental results show that the values of the equilibrium constants and absolute free energy of partition of Vitamin K3 are smaller than those of zinc oxide nanoparticles.
It is found that both the sizes of the micelles and the sizes of the nanoparticles will affect the critical micelle concentrations of the copolymers, average sizes of the micelles, equilibrium constants, and the free energy of partition. In comparison of two factors, the influence caused by the sizes of the micelles is more obvious.

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