Monodisperse microspheres as drug release system prepared by Shirasu porous glass (SPG)

膜乳化法是将分散相在压力的作用下透过膜孔而在另一侧膜表面形成液滴，在流动的连续相的冲刷下从膜表面剥离，从而形成粒径均一的乳液。用膜乳化法制备乳液具有操作简单、能耗小、易于控制液滴大小、乳液单分散性好、稳定性高等许多优点，可用于功能性单分散微球和微囊的制备。同时为弥补此法难以制备1µm以下的纳米颗粒的不足，本研究直接利用本实验室已有的研究成果，以透析法制备了纳米级的单分散性载药颗粒。 本论文以聚乳酸（PLA）为药物载体，使用微孔膜乳化器发展操作简单、粒径可控、易于规模化生产的微囊（球）的制备方法；以羟基喜树碱（HCPT）为模型药物，制备高载药量和包封率的缓释微球，并初步探索制备了植...By employing Shirasu Porous Glass (SPG) emulsification technique, uniform polymer microspheres can be obtained. Disperse phase are permeated the holes through the SPG membrane by the press to form globelets and then rushed away by the continue phase. SPG emulsification is a simle and manageable technique. This way also has advantages such as lower wasted power, excellent homogenization and good st...学位：工学硕士院系专业：材料学院生物材料系_生物医学工程学号：2402005130255

透析法制备载羟基喜树碱-聚乳酸纳米粒及其理化性质研究

采用直接透析法制备载羟基喜树碱-聚乳酸(HCPT-PLA)纳米粒并研究其理化性质、体外释放和细胞毒性.以HCPT-PLA纳米粒的载药率为评价标准,通过正交设计考察PLA浓度、HCPT与PLA的质量比和不同截留分子质量透析袋对其指标的影响.利用Malvern nano-zs粒度测定仪、XRD、DSC和激光共聚焦显微镜(CLSM)对HCPT-PLA纳米粒的理化性质进行表征.薄膜透析法考察体外释药特性;MTT试验检测细胞毒作用.在优化条件下制备的载药纳米粒为实心球形,平均粒径为226.8 nm,多分散系数为0.270,载药率为7.49%.HCPT是以晶体状态均匀分布于PLA纳米粒中.药物体外释药符合Higuchi方程Q=2.000 6X1/2-2.593 4,r=0.989 2.MTT试验显示HCPT-PLA纳米粒呈现明显细胞毒作用.透析法制备HCPT-PLA纳米粒,粒径小且分布均匀,具有较好的缓释特性;细胞毒性试验表明HCPT-PLA纳米粒具有较强的抑瘤作用且抑瘤效果优于HCPT

纳米级载药微泡的制备及其超声介导下的抑瘤研究

具有超声造影剂和药物载体双重功能的聚乳酸(PLA)微泡存在着载药率较低以及不能有效地透过肿瘤组织等缺点.对此,以PLA和卵磷脂为药物载体,采用改良的超声复乳法制备载紫杉醇的PLA-卵磷脂纳米级微泡.考察了卵磷脂对载药微泡理化特性(包括:形态、粒径、载药量、包封率和体外释药特性)的影响,利用X-射线衍射分析(XRD)考察了药物在微泡中的状态,最后在超声介导下对荷瘤小鼠的抑瘤率进行了研究.结果表明,卵磷脂与PLA质量比为50∶250时可制备得到平均粒径615 nm、内部空心的纳米级微泡,药物包封率达(90.90±5.79)%,载药率为(8.26±0.53)%,紫杉醇以无定型状态分布在微泡的壳中.微泡的体外药物释放具有缓释、零级释放以及超声介导加快药物释放的特性,而通过对H22肝癌荷瘤小鼠的实验研究表明,相对于紫杉醇针剂而言,超声介导下载药PLA-卵磷脂纳米级微泡注射剂能减小对小鼠的毒副作用,提高抑瘤率

Inhibitory effect of mitomycin C-loaded controlled release collagen implant on the growth of hepatocellular carcinoma in nude mice

目的研究植入式丝裂霉素(mitomycin C-loaded collagen,MMC)控释膜剂对人肝癌裸鼠移植瘤的抑瘤作用。方法:将0．06、0．12、0．18 mg三种不同剂量的MMC控释膜剂植入荷人肝癌裸小鼠皮下移植瘤内,并与用相同剂量的瘤内注射、腹腔注射及对照组比较,观察其抑瘤作用。结果:0．18 mg MMC瘤内植入组抑瘤率明显高于对照组(P＜0．01)及0．06 nag MMC瘤内植入组(P＜0．05);0．18 mg MMC控释膜剂瘤内植入组抑瘤率也明显高于0．18 mg MMC腹腔注射组(P＜0．01)。结论:植入式MMC控释膜剂可能是一种有效治疗原发性肝癌的药物新剂型。 【英文摘要】 Objective:To study the inhibitory effect of controlled release mitomycin C(MMC)-loaded collagen implant on the growth of hepatocellular carcinoma in nude mice.Methods:Three different doses(0.06.0.12,and 0.18 mg)of controlled release mitomycin C-loaded collagen implant were implanted into the transplanted human hepatocellular carcinoma(LCI-D20)in nude mice.The inhibitory effect on tumor growth was observed and compared with intratumoral injection,intraperitoneal injec- tion.and control group at the same dosa...厦门市科技计划资助项目(编号:3502720055007

Production of paclitaxel loaded PLA-lecithin ultrasound contrast agents

Conference Name:2013 International Conference on Bio-Medical Materials and Engineering, ICBME 2013. Conference Address: Hong Kong, China. Time:March 26, 2013 - March 27, 2013.Drug loaded PLA (or PLGA) mirobubbles that combine properties of ultrasound imaging contrast agents and drug carriers suffer from low encapsulation efficiency and difficulty to destruction with diagnosis ultrasound. In this paper, a new type of multifunctional paclitaxel-loaded poly lactide-lecithin(PLA-lecithin)microbubbles has been developed with a method of ultrasonic double emulsion solvent evaporation (UDES) combined with lyophilization, and single-factor of ultrasonic time was studied to influence bubble size and drug loading efficiency. Bubbles were characterized to be well dispersed, with size of 300nm~2um, and showed increased ultrasound imaging on rabbit liver and heart after intravenous injection. ? (2013) Trans Tech Publications, Switzerland

Formation of breath figure arrays in methanol vapor assisted by surface active agents

Breath figure (BF) process is a promising technique for fabricating honeycomb polymer films. It is usually conducted in water vapor. While, in organic vapors only unique polymer can be used to prepare BF arrays as reported in our previous article (Breath Figure in Nonaqueous Vapor. Soft Matter, 2013, 506-514), although new structure features are induced in the film. In this paper, a universal modified BF processing is devised for preparing porous films in methanol vapor with conventional polymers, by adding a small amount of surface active agent into the casting solution, such as siloxane- and fluorine-containing block copolymers. The pores in the PS films prepared with this method are of cylindrical shape with large depth-diameter aspect ratio, and the diameter and depth of pores can be well controlled by the experiment conditions. Based on these results, the formation mechanism of honeycomb structure in methanol vapor is discussed. ? 2014 American Chemical Society

Development of multifunctional folate-poly(ethylene glycol)-chitosan-coated Fe3O4 nanoparticles for biomedical applications

The efficacy of magnetic nanoparticles (MNPs) for biomedical applications depends on the specic targeting capacity, blood circulation time and magnetic susceptibility. Functionalized chitosan-coated Fe3O4 nanoparticles (CS-coated Fe3O4 NPs) were synthesized by a non-solvent-aided coacervation procedure followed by a chemical crosslinking procedure. The surfaces of CS-coated Fe3O4 NPs were successfully functionalized with folate-poly(ethylene glycol)-COOH (FA-PEG) to obtain novel FA-PEG-CS-coated Fe3O4 NPs endowed with long blood circulation and specic targeting capacity. The as-synthesized NPs were characterized by dynamic light scattering, transmission electron microscope, X-ray diffraction, thermal gravimetric analysis, vibration sample magnetometer, Fourier transform infrared spectroscopy, and confocal laser scanning microscopy. As a result, the novel FA-PEG-CS-coated Fe3O4 NPs showed excellent biocompatibility, magnetic properties, good dispersibility, and proper hydrodynamic sizes in an aqueous medium. The specific targeting capacity of the as-synthesized NPs to cancer cells was also investigated. It was observed that the uptake of the FA-PEG-CS-coated Fe3O4 NPs by HeLa cells was significantly enhanced compared to the CS-coated Fe3O 4 NPs and mPEG-CS-coated Fe3O4 NPs. These results clearly indicate that our novel FA-PEG-CS-coated Fe3O 4 NPs with remarkable specific targeting capacity, long blood circulation, and superparamagnetism hold great promise for biomedical applications, including targeted drug delivery and hyperthermia therapy. [Figure not available: see fulltext.] ? 2014 The Polymer Society of Korea and Springer Sciene+Business Media Dordrecht