1、扇型/線型-線型論文：扇型一線型聚賴氨酸共聚物的合成、自組裝及其水凝膠的構筑【中文摘要】本論文以扇型/線型結構的聚賴氨酸 Dm-PZLys 為前 聚體,通過與 PEO 吉合,得到了一系列扇型/線型-線型的可降解及具 有生物相容性的嵌段聚合物，并通過脫除賴氨酸側鏈氨基的保護基團 得到聚陽離子共聚物。（1）點擊化學和開環聚合方法制備扇型-線型 Dm-PZLys-b-PEO嵌段共聚物及其表征利用具有“點擊”功能化的端 炔基化聚酰胺-胺，采用“點擊”化學（Click Chemistry） 和開環聚合 （ROP）的方法,設計合成了扇型/線型-線型聚（-芐氧羰基-L-賴氨酸）嵌段共聚物，通過利用紅外光譜、

2、核磁氫譜、凝膠滲透色譜、差示掃 描量熱儀、偏光顯微鏡、廣角 X 射線衍射等對嵌段共聚物的化學結構 與物理性能進行了詳細的表征;PZLys鏈段在聚賴氨酸均聚物和共聚 物中均出現了液晶相的轉變，并且這種轉變是不可逆的。同時，隨著 PZLys 鏈段組成的增加,PEO 鏈段在線性共聚物中的結晶度從 96.2 % 降至 20.4 %,而扇型-線型共聚物中的 PEO 鏈段的結晶完全受到了抑 制；隨著鏈長的增加,PZLys 鏈段的二級結構從?-折疊構象向?-螺旋構 象轉變。 這一系列的共聚物可在水溶液中組裝成球形納米粒子，阿霉 素作為模型藥物，負載后對共聚物組裝形成納米粒子的形貌幾乎沒有影響；所有的阿霉素載

3、藥納米粒子在 pH 7.4 及 pH 5.5 條件下表現三 相釋放模式，釋放周期長達兩個月。（2）扇型-線型共聚物 Dm-PLys-b-PEO勺合成、性能表征，以及超分子水凝膠的制備在前面合成的 Dm-PZLys-b-PEO 基礎上，利用脫保護化學，得到了聚陽離子共 聚物 Dm-PLys-b-PEO 利用紅外光譜、核磁氫譜、廣角X 射線衍射、偏光顯微鏡、動態光散射等對共聚物的化學結構、物化性能及自組裝性能進行了表征。運用主-客體化學和聚氨基酸鏈段之間的氫鍵相互 作用,初步探索利用同一種聚賴氨酸基兩嵌段共聚物來構筑“普通膠 束水凝膠”和“反膠束水凝膠”，這種超分子水凝膠是通過聚(L-賴氨 酸)鏈

4、段之間的氫鍵相互作用以及聚乙二醇與-環糊精間的包絡作用 而共同形成的，并利用廣角 X 射線衍射、差示掃描量熱儀等表征手段 對超分子水凝膠的物化性能和成膠機理進行了初步的探索?！居⑽恼緿en dro nlikepoly(?-be nzyloxycarb on yl-L-lys in e)/li near poly(ethyle neoxide) block copolymers (i.e., Dm-PZLys-b-PEO, m = 0 and 3; Dm are thepropargyl focal point poly(amido amine) dendrons having 2m pri

5、maryamine groups) were for the first time syn thesized by comb ining rin g-opening polymerizati on (ROP) of ?-be nzyloxycarb on yl-L-lys ine N-carboxyanhydride (Z-Lys-NCA) and click chemistry, where Dm-PZLyshomopolypeptides were click conjugated with azide-term in ated PEO.Then through the deprotect

6、i on of ben zyloxycarb onyl group on the PZLysblock, Dm-PLys-b-PEOwere achieved.(1)Synthesisand Characterizati on of Dendron-like/Li near Dm-PZLys-b-PEOCopolymers via ROP and Click Chemistry A new class ofdendron-like/li near Dm-PZLys-b-PEO block copolymers was syn thesizedvia con trolled rin g-ope

7、ning polymerizati on (ROP) of Z-Lys-NCA followedby a click conjugatio n with azide-term in ated poly(ethyle ne oxide)(PEO-N3). Their molecular structures and physical properties werecharacterized in detail by FT-IR, 1H NMR, gel permeation chromatography,differe ntial sca nning calorimetry, polarized

8、 optical microscopy, and widean gle X-ray diffracti on. Both homopolypeptides and copolymerspresented a liquid crystalline phase transition for PZLys block, and thetransition was irreversible. Moreover, the degree of crystalli nity of PEOblock with in lin ear copolymers decreased from 96.2 %to 20.4

9、% withincreasingPZLys composition, while that within dendriticcopolymers decreased to zero. The sec on dary con formati on of PZLysprogressively cha nged from -sheet to -helix with in creas ing the cha in length. These copolymers self-assembled into spherical nano particles inaqueous soluti on, and the an tica ncer drug doxorubic in-loaded nanoparticles gave a similar morphology compared to their bla nk coun terparts.The drug-loaded nan oparticles showed