镁掺杂纳米羟基磷灰石的制备及其在载药方面的应用

通过逐步沉淀反应一锅法制备了一系列不同含量的镁掺杂纳米羟基磷灰石。通过硝酸镁、硝酸钙不同的投料物质的量比调控纳米颗粒的形态和尺寸。通过透射电子显微镜(TEM)、X射线衍射(XRD)等分析手段对镁掺杂纳米羟基磷灰石进行物理化学性能表征,用MTT法评价其体外细胞毒性。研究结果表明:镁掺杂纳米羟基磷灰石呈现束状纳米纤维形态、比表面积大、细胞毒性较低;将其作为载体负载抗癌药物顺铂,具有很好的载药能力,载药量可达54%,该载药纳米颗粒还具备缓释特性(72 h释药量达到41.72%)和很好抑制癌细胞生长的效果。     

石墨烯纳米载药体系的制备及对肿瘤细胞的杀伤作用

通过聚乙二醇(PEG)及分支型聚乙烯亚胺(bPEI)对纳米氧化石墨烯(NGO)修饰作为大分子载药基底的载药平台,增加了NGO的水溶性及其对蛋白的吸附作用,随后分别负载抗癌药物顺铂(CDDP)和低温乙醇法分离提纯的肿瘤患者血清形成能够特异性富集于鼻咽癌细胞的大分子石墨烯纳米载药体系。通过紫外-可见光谱和傅里叶变换红外光谱表征结果证实NGO-PEG-bPEI-CDDP载药体系制备成功,NGO-PEG-bPEI对CDDP的载药率为34.6%。聚丙烯酰胺凝胶电泳(SDS-PAGE)表明对NGO-PEG-bPEI-CDDP-Antibody大分子纳米载药体系中特异性抗体蛋白的强烈吸附作用,该纳米复合物能够特异性地富集在肿瘤细胞部位,对人鼻咽癌细胞(CNE-1)细胞系的识别极其敏感。细胞毒性实验(MTT)检测实验结果表明:在相同剂量(质量浓度)、相同作用时间的情况下,NGO-PEG-bPEI-CDDP-Antibody大分子纳米石墨烯载药体系兼具对人口腔鳞癌细胞(KB)、CNE-1杀伤作用和避免正常细胞的额外损伤。NGO-PEG-bPEI-CDDP-Antibody纳米载药体系不仅能够通过特异性识别将药物富集于病灶区降低正常细胞损害,还能够有效杀伤癌细胞,降低化疗药物使用剂量,是一种很有前景的大分子纳米载药体系。     

镁掺杂纳米羟基磷灰石的制备及其在载药方面的应用

通过逐步沉淀反应一锅法制备了一系列不同含量的镁掺杂纳米羟基磷灰石。通过硝酸镁、硝酸钙不同的投料物质的量比调控纳米颗粒的形态和尺寸。通过透射电子显微镜（TEM）、X射线衍射（XRD）等分析手段对镁掺杂纳米羟基磷灰石进行物理化学性能表征,用MTT法评价其体外细胞毒性。研究结果表明：镁掺杂纳米羟基磷灰石呈现束状纳米纤维形态、比表面积大、细胞毒性较低;将其作为载体负载抗癌药物顺铂,具有很好的载药能力,载药量可达54%,该载药纳米颗粒还具备缓释特性（72 h释药量达到41.72%）和很好抑制癌细胞生长的效果。     

石墨烯纳米载药体系的制备及对人口腔鳞癌细胞杀伤效果

利用化学氧化还原法制备了氧化石墨烯,进一步超声破碎剥离,得到纳米氧化石墨烯,并对其进行聚乙二醇(PEG)的功能化修饰后载药顺铂。 采用扫描电子显微镜(SEM)、紫外-可见吸收光谱(UV-Vis)、傅立叶变换红外光谱(FTIR)对石墨烯纳米载药体系进行表征,细胞存活率实验(MTT)法检验石墨烯纳米载药体系对人口腔鳞癌(KB)细胞的杀伤作用。 结果表明,石墨烯纳米载药体系对顺铂的负载率为42.4%,聚乙二醇修饰后可以降低纳米氧化石墨烯的细胞毒性并提高生物相容性,对KB细胞具有双重的杀伤作用,为纳米氧化石墨烯在肿瘤治疗的临床应用提供了理论依据。     

自组装型紫杉醇键合物前药的合成与性能

以p-氨基苯乙酸(APA)和六亚甲基二异氰酸酯(HDI)为连接基团,将短链聚乙二醇单甲醚(mPEG)键合到紫杉醇(PTX)上,获得双亲型PTX前药mPEG-APA-PTX和mPEG-HDI-PTX.考察了这两种前药在自主装、体外药物释放动力学、体外细胞毒性和体内血浆清除速率等方面的表现.结果表明:两前药均能在水中自组装形成稳定的纳米颗粒,载药量高达28％;mPEG-HDI-PTX纳米颗粒在水溶液中非常稳定,细胞毒性很弱,在血液系统中清除很快,而mPEG-APA-PTX纳米颗粒在pH=7.4的环境下可缓慢释放出原药PTX,细胞毒性与临床用紫杉醇针剂Tax-ol(R)相当,体内循环时间较Taxol(R)明显延长;mPEG-APA-PTX是一种可自组装、载药量高、体内循环时间长的新型纳米前药.     

pH和还原双重敏感性超支化纳米胶束的制备及其释药性能

将聚乙二醇二缩水甘油醚(PEGDGE)与胱胺(Cys)置于水溶液中,通过亲核开环反应制备出超支化聚合物,并自组装形成多核-壳结构的纳米胶束,再通过甲氨蝶呤(MTX)与纳米胶束间的疏水作用制备出载药胶束。用FT-IR、~1H-NMR、DLS、SEM等方法对聚合物结构和胶束粒径与形貌进行表征,采用噻唑蓝(MTT)法测试纳米胶束和载药胶束的细胞毒性。结果表明:聚合物经过透析纯化后自组装形成纳米胶束,其粒径约为100nm,呈均一球形;载药胶束对MTX的载药率为10.32%;当载药胶束处于模拟肿瘤环境中时,酸性和还原性条件可刺激药物释放。细胞毒性实验表明,纳米胶束具有优良的生物相容性;载药胶束具有较强的抗肿瘤活性。     

热处理温度对溶剂热合成Co3O4纳米片气敏和吸附性能之影响

以Co（Ac）₂·4H₂O和六次甲基四胺（HMTA）为起始反应物,聚氧乙烯-聚氧丙烯-聚氧乙烯（P123）为表面活性剂,在乙二醇（EG）和水混合溶剂中用溶剂热法得到中间产物,通过煅烧热处理制备了Co₃O₄纳米片。利用XRD、SEM和N₂吸附-脱附等方法进行了样品表征,研究了不同热处理温度对产物形貌和结晶度的影响,以及所制备纳米片的气敏性能。根据气敏测试和吸附性能结果,分析了气敏机理和吸附动力学。结果表明：热处理温度是影响产物形貌的关键因素,350℃是最佳的热处理温度,此时得到的纳米片最薄也最均匀。由于产物形貌变化改变了材料的比表面积,进而影响到产物的气敏性能和吸附性能。总体而言,纳米片厚度越小,比表面面积越大,材料的气敏灵敏度和吸附效率越高。     

白蛋白原位复合的生物医用功能材料的研究(Ⅱ)──白蛋白的选择性吸附和血液相容性研究

采用¹²⁵I放射标记技术研究了血浆白蛋白和纤维蛋白原在聚甲基丙烯酸甲酯-接枝-十八烷基聚氧乙烯(PMMA-g-SPEO)、聚甲基丙烯酸甲酯-接枝-乙基聚氧乙烯(PMMA-g-EPEO)和聚甲基丙烯酸甲酯-甲基丙烯酸十八酯共聚物(PMMA-co-SMA)表面的竞争吸附行为.结果表明,十八烷基聚氧乙烯复合修饰的PMMA-g-SPEO可高选择性地形成白蛋白可逆吸附层,有效地阻抗血小板的粘附,延长材料的凝血时间,是一种理想的白蛋白原位复合的生物医用功能材料.     

以混合阳离子-嵌段共聚物表面活性剂为模板合成介孔MCM-48

利用阳离子和嵌段共聚物混合表面活性剂为模板,在水热条件、碱性介质中成功地合成出MCM-48介孔分子筛。在1TEOS(正硅酸乙酯)∶0.125CTAB(十六烷基三甲基溴化铵)∶nP123(聚氧乙烯-聚氧丙烯-聚氧乙烯三嵌段共聚物)∶0.50NaOH(氢氧化钠)∶61H₂O(物质的量的比)体系中,n值在较大范围内(0.000 625～0.018 75)可调。通过粉末X射线衍射(XRD)、N₂物理吸附、扫描电镜(SEM)对合成样品进行表征。结果表明：聚氧乙烯-聚氧丙烯-聚氧乙烯三嵌段共聚物(P123)的加入可以更大程度地降低合成MCM-48所需阳离子表面活性剂的用量;合成的MCM-48具有高比表面积、高度有序的孔道结构、较集中的孔径分布和较高的热和水热稳定性。     

γ-聚谷氨酸/壳聚糖纳米颗粒的制备及pH响应释放性能

利用生物相容性良好的γ-聚谷氨酸(γ-PGA)和壳聚糖(CS)制备表面分别带正、负电荷的pH响应性纳米颗粒,并用其包载抗生素阿莫西林。利用动态光散射仪、傅里叶红外光谱仪、X射线衍射和透射电镜对载药纳米颗粒的结构和形貌进行表征,考察两种纳米载体的pH响应释放药物能力及其对细胞的毒性。研究结果表明,带负电荷的纳米颗粒显示出更好的pH响应控释药物的能力。在模拟胃部环境下,载药纳米颗粒的粒径大小稳定在200～300 nm,药物释放量仅为25%。在中性至弱碱性的肠道细胞间隙下,其粒径增大到1μm左右,药物释放量增加到85%。此外,细胞毒性实验表明该药物载体对细胞没有毒性,载药纳米颗粒对肠道细菌的抑制效果比游离药物的更好。     

载药脂质体复合缺钙磷灰石骨水泥支架的研究

采用食盐颗粒浸出法制备了缺钙磷灰石水泥(CPC)多孔支架;用脂质体包裹盐酸万古霉素制备了载药脂质体。将它们两者结合,制备了脂质体载药复合缺钙磷灰石水泥(dl-CPC)支架。结果表明:缺钙CPC多孔支架能够将载药脂质体吸附在其大孔表面或微孔里;dl-CPC支架对MC3T3-E1细胞的生长没有负面影响,显示出良好的细胞相容性。此外,dl-CPC支架具有很好的抗菌性能,能够抑制大肠杆菌生长,抗菌率达99%(12 h)。dl-CPC支架浸泡在磷酸缓冲溶液中,释放药物的速度比较缓慢(前4周);而直接吸附药物的CPC支架,在1周内大部分药物释放出来,出现暴释现象。另结果表明:dl-CPC支架具有缓释药物和骨再生的双重功能,可用于骨缺损的修复及治疗慢性骨髓炎。     

Hierarchical meso–macroporous bioglass for bone tissue engineering

A novel meso–macroporous bioglass has been synthesized based on a sol–gel technique. This method used mushroom stalk as macroporous template and EO₂₀PO₇₀EO₂₀ as the mesoporous template. The final sample has copied the macroporous structure of the plant template, precisely. Ibuprofen was used as the model drug, and the drug loading and release test indicated the loading amount of the sample could reach 33.59 wt% and the releasing amount closed 75 wt% after 48 h. The excellent biomineralization and bioactive are also confirmed in vitro tests. It takes only 4 h to induce the formation of hydroxyapatite. Notably, the biocompatibility assessment confirmed that the obtained materials presented good biocompatibility and the enhanced adherence of HeLa cells. The exquisite mesoporous structure of the sample would be propitious to storage and transport guest molecule, making the hierarchical porous materials have more distinctive performance and application on bone tissue regeneration and drug delivery, etc.     

不同结构颗粒对PMMA基复合材料性能影响

采用原位本体聚合法制备PMMA/MCM-41(with template),PMMA/SBA-15(with template),PMMA/SiO2三种复合材料.研究了介孔分子筛MCM-41,SBA-15和SiO2对PMMA复合材料拉伸强度,冲击强度,热稳定性的影响.由于合成介孔分子筛MCM-41,SBA-15时所用的模板剂CTAB和P123分布于孔口处和颗粒表面上,分别与PMMA基体产生物理缠结作用,增加了两者的相容性;且P123(EO20PO70EO20)表面有较大的PO/EO比率,与小分子量的CTAB相比有较强的疏水性,使得PMMA/SBA-15(with template)复合材料的性能要优于PMMA/MCM-41(with template).     

Aqueous foam stabilized by polyoxyethylene dodecyl ether

Foaming properties of aqueous solutions of the nonionic surfactant polyoxyethylene dodecyl ether (C₁₂EO _n ) were studied at 298 K. Four different EO chain lengths, namely C₁₂EO₃, C₁₂EO₅, C₁₂EO₇, and C₁₂EO₉, were considered. The foams obtained from C₁₂EO₃ or C₁₂EO₅ were extraordinary stable retaining a constant volume for more than 20 h. The presence of lamellar liquid crystalline phases was mainly responsible for the super-stable aqueous foams.     

Synthesis and Characterization of Ordered Mesoporous Silica Spheres Using Anionic and Nonionic Mixed Surfactants for Their Potential Application in LC

Ordered mesoporous silicas (OMSs) with spherical morphology were synthesized by using mixed surfactants of anionic sodium dodecyl sulfate and nonionic block copolymer EO₂₀PO₇₀EO₂₀ (P123) as template through an acid-catalyzed silica sol?Cgel process. A variety of characterizations demonstrated that the silica products exhibited well-formed spherical morphology, ordered mesostructure, narrow pore size distribution and large surface area (~700 m² g^?1). It was found that the synthesized OMSs had high adsorption capacity by using oxymatrine as model solute. The column packed with the silica spheres exhibited low back pressure and baseline separation of aromatic compounds such as benzene and nitrobenzene could be achieved. These results demonstrated the synthesized OMSs as a potential stationary phase for liquid chromatography.     

The effect of recrystallization time on pore size and surface area of mesoporous SBA-15

Triblock copolymer, pluronic P123 (EO₂₀PO₇₀EO₂₀) was used as the structure directing agent for the simple synthesis and characterization of mesoporous SBA-15 with various porosities. Extending the sample recrystallization time, after the initial synthesis and ageing, seems to have a significant effect on the pore size. It also leads to an increase in the surface area and a narrow pore size distribution. The prepared materials could find applications in areas where the diffusion of large molecules is important, and in catalysis, where greater pore accessibility would enhance the activity and selectivity of the catalyst. A possible mechanism has been proposed to describe the effect of extended recrystallization on pore sizes.     

Preparation of WO<Subscript>3</Subscript>-SBA-15 mesoporous molecular sieve and its performance as an oxidative desulfurization catalyst

The tungsten-containing mesoporous molecular sieve WO₃-SBA-15 (SBA: Santa Barbara Amorphous type materials) was prepared under conventional hydrothermal conditions in strong acidic solution using H₂WO₄ as tungsten source, tetraethyl orthosilicate as silicon source, and a mixture of P123 tri-block copolymer (EO₂₀PO₇₀EO₂₀) and cetyltrimethylammonium bromide as structure-directing agent. The catalyst was tested for oxidative desulfurization and characterized by X-ray diffraction and nitrogen adsorption–desorption. The catalyst had the highest desulfurization performance (i.e., 91.3%) after oxidation under the following reaction conditions: 20 mL gasoline with 540 ppm sulfur, 6 mol H₂O₂/sulfur, reaction temperature 333 K, reaction time 80 min, and three extraction cycles.     

Fabrication of ZnO Nanorods in Colloidal Systems Formed by PEO‐PPO‐PEO Block Copolymers

One‐dimensional (1‐D) ZnO nanorods with various sizes were synthesized in colloidal systems formed by PEO‐PPO‐PEO block copolymers. The experimental results revealed that the growth of ZnO nanorods was dependent on the molecular structure of polyether. It was known that L64 (EO₁₃PO₃₀EO₁₃) and F68 (EO₈₀PO₃₀EO₈₀) had the same size PPO block but different content of PEO. We concluded that the size of the ZnO products obtained in F68 was larger due to its longer PEO chain.     

纳米TiO2介孔薄膜的模板组装制备研究

以TiCl₄为无机前驱体、三嵌段高分子共聚物EO₂₀PO₇₀EO₂₀为模板剂，在非水条件下制备了有序的锐钛矿TiO₂纳米晶介孔薄膜。通过热重-差热（TG-DTA）分析、X射线衍射（XRD）分析、原子力显微观察（AFM）及N₂吸附-脱附等测试对样品进行了表征。结果表明，薄膜具有均一的大介孔孔径（～10 nm），其BET比表面积为150 m²·g^-1，薄膜较宽的无机壁厚显著提高了介孔结构的热稳定性。通过红外（IR）光谱分析考察了溶胶-凝胶过程中发生的物理化学变化。在对薄膜表面形貌进行AFM观察的基础上初步探讨了嵌段共聚物EO₂₀PO₇₀EO₂₀对薄膜孔结构形成的导向机理。     

Vapor Pressures of Phenethyl Alcohol in the System Water-Phenethyl Alcohol and the Triblock Copolymer EO4.5PO59 EO4.5

ABSTRACT

The phase diagram of water, phenethyl alcohol (PEA) and the triblock copolymer EO_4.5PO₅₉EO_4.5, (EO = ethylene oxide, PO = propylene oxide), L101, was determined and the vapor pressures of PEA were measured for different phases.

The phase diagram was almost identical to the corresponding one with a simple nonionic surfactant, Laureth 4, (?C₁₂EO₄), but the PEA vapor pressure variation with mole fraction was significantly different reflecting the strong molecular interaction between PEA and the polymer. This distinction was mainly due to difference in molecular size; vapor pressure plots against weight fraction gave curves with only moderate variance.

The results were used to discuss the variation in the PEA vapor pressure with time after application of a vesicular solution of PEA stabilized either by L101 or Laureth 4. The moderate differences in vapor pressures had a significant influence on the estimated curves of PEA pressure versus time.