Preparation of lung targeting microspheres of gelatin ceftiofur alkali

Gelatin ceftiofur alkali microsphere was prepared to observe its characteristics and evaluate preservation conditions. The glutaraldehyde was increased and the carboxylic methyl chitosan was added to improve the microsphere. The experimental results show microspheres have a better morphology surface and fairly regular structure with 4% glutaraldehyde. The average particle size is 15.84 μm and particle size distribution is narrow which shows a good uniformity. Microsphere size was affected by the stirrer speed, dosing ratio and curing degree. The greater drug loaded is, the better microspheres loading is; but with the increase of drug loading rate, the entrapment efficiency increases first and then decreases. The drug release rate of the microsphere is 24.90% in 0.5 h and 84.90% in 48 h, when CMC-GMs with 4% curing agent is 32.03% in 0.5 h and 88.44% in 48 h. So Gms embedding of ceftiofur alkali are better than CMC-GM. The stability tests show that strong light, high temperature, high humidity have a great influence on the microspheres.     

Preparation of PLGA ceftiofur hydrochlorate lungtargeted microsphere with spray drying process

To explore the preparation of PLGA ceftiofur hydrochlorate lung-targeted microsphere with spray drying process, the preparation technics was optimized by orthogonal experiments. Appearance, particle size, drug-loaded properties and medicine dissolution rate of the microsphere were evaluated. The experimental results show that the prepared PLGA microspheres loaded with ceftiofur hydrochlorate have good appearance, good encapsulate rate and dissolution. The drug loading capacity of ceftiofur-hydrochlorate-loaded PLGA microsphere prepared with spray drying process is 23.06%, i e, when the dosing ratio is 1：3, the encapsulate rate is 92.23% at maximum, and the release percentage of medicine is at 0.5 h. The medicine is released almost completely at 20 h and the accumulated medicine release is 98.12%.     

Optimization of the process of gelatin-ceftiofur sodium microspheres

Gelatin microsphere(GMS) was prepared through W/O emulsion chemical-crossline method.The best formula was selected by examining its appearance,size,drug carrier and drug dissolution rate.The experimental results showed that the optimized gelatin microspheres were spherical ball with smooth surface and had well dispersion.The average size of blank gelatin microspheres was 15.84 μm,while the loaded microspheres'average diameter were 33.10 μm.It was also shown that drug loading of microspheres increased with increasing loading capacity,but drug encapsulation efficiency had a trend of climbing up and then decline.The encapsulation efficiency reached the maximum when the dosage ratio was 2:1.And the results show ceftiofur sodium microspheres have sustained release in the PBS buffer of pH7.4.     

京尼平交联壳聚糖微球的制备及理化性质

以壳聚糖为原料,京尼平为交联剂,采用乳化化学交联法制备壳聚糖载药微球,并利用单因素试验方法得出最佳制备工艺条件。采用扫描电镜（SEM）、显微镜、傅里叶红外光谱（FT—IR）及紫外光谱（UV）等现代仪器和对其形貌结构、反应机制等进行研究。结果表明：最佳工艺条件为温度30℃,10mL的6g／L的壳聚糖乙酸溶液（2％,WV）,京尼平溶液（70g／L）6mL,油水比为1：5。交联机制为shift反应机制。     

壳聚糖／明胶磁性微球的反相悬浮乳液包埋法制备研究

在油包水（W／O）体系中,采用反相悬浮乳液包埋法,以戊二醛为交联剂,实现了壳聚糖和明胶（Gs／Gel）微球对Fe304磁性粒子的包裹．其制备的磁性微球粒径在3～8μm范围,分散性和磁响应性良好;磁性微球可较好地吸附BSA和亲和层析兔抗β-CNIgG,对后者的吸附率在48h稳定后可达到42．75％,为实验室制备高质量免疫磁性微球奠定了基础．     

微米级壳聚糖微球的制备

利用液体石蜡作有机分散介质、戊二醛作交联剂,通过反相悬浮交联法制备了微米级壳聚糖微球,并研究了反应条件对壳聚糖微球制备的影响。结果表明,壳聚糖溶液质量分数为4.5%、液体石蜡和壳聚糖溶液两相体积比1∶1.5、Span-80在油相中的质量浓度为9.0mg/mL、戊二醛和壳聚糖溶液体积比1∶20、搅拌转速大于800r/min时,SEM表明所制备产物是粒径10μm的壳聚糖微球。壳聚糖微球对活性物质具有一定的吸附能力。     

Preparation of Magnetic Fluorescent Dual-drug Nanocomposites for Codelivery of Kaempferol and Paclitaxel

Magnetic fluorescent dual-drug nanocomposites(MFDDs) were developed with the aim of simultaneouly delivering two different anticancer drugs, kaempferol(KAE) and paclitaxel(PTX). Firstly, Fe_3O_4/bovine serum albumin(Fe_3O_4/BSA) composite microspheres with physically entrapped KAE were prepared, then microspheres were modified with PTX/graphene quantum dots(PTX/GQDs) through chemically bonding, and the MFDDs were obtained. The properties of nancomposites were characterized by X-ray diffractometry, Fourier-transform infrared spectroscopy, transmission electron microscopy, vibrating sample magnetometry and X-ray fluorescence spectrometry. It was found that the superparamagnetic nanocomposites had ultrafine size(below 110 nm), high saturation magnetization of 24.36 emu/g, and significant fluorescence. Furthermore, the cumulative in vitro release of the MFDDs exhibited controlled drug release. Cell viability experiments confirmed that the co-administration of KAE with PTX had a superior cytotoxicity to the Hela cells compared with single drug-loaded forms. Therefore, dual anticancer drug-loaded MFDDs have the potential to be used for cancer combined chemotherapy.     

交联QCS／PS阴离子交换膜的制备及表征

以壳聚糖（CS）为原料,2,3-环氧丙基三甲基氯化铵为醚化剂,通过亲核取代反应,将季铵基团引入壳聚糖主链,制备季铵化壳聚糖（QCS）。采用阳离子季铵盐十六烷基三甲基溴化铵和引发剂过硫酸钾,通过乳液聚合法合成了聚苯乙烯（PS）微乳液。以QCS为膜的基本原料,掺杂了适量的PS微乳液,以戊二醛为交联剂,制备了一系列的OCS／PS阴离子交换膜。用傅立叶变换红外光谱（FT—IR）表征了样膜的结构,考察了PS微球和戊二醛含量对QCS／PS膜的吸水性和离子交换量等性能的影响。结果表明,交联剂的加入可有效抑制QCS膜的形变,在PS微球质量分数为35％时,随着交联度的增加使溶胀度从68．5％降低到25．8％,但同时降低了QCS／PS膜的离子交换量。而PS微球却提高了OCS／PS膜的离子交换量,溶胀度也略有降低。因此当交联度为5％、PS微球质量分数为35％时,含水率为65％,IEC为4．89mmol／g,二者都达到了稳定的趋势,能够优化Qcs／Ps膜的整体性能。     

壳聚糖为基质的左氧氟沙星缓释微球制备

以壳聚糖为基质,对左氧氟沙星缓释微球的制备方法进行了探索.确定了左氧氟沙星-壳聚糖缓释微球的制备工艺条件.通过考察微球的载药量及累积释放度,对上述制备方法工艺中的壳聚糖与盐酸左氧氟沙星的质量比、乳化剂Span用量、溶剂与壳聚糖溶液的体积比、交联剂戊二醛用量等因素进行了优化,制备出了具较好缓释效果的盐酸左氧氟沙星-壳聚糖缓释微球.该方法制备的左氧氟沙星-壳聚糖缓释微球载药量为43.88%,体外累积释放度的线形关系良好.     

羟丙基壳聚糖-胰岛素微球的制备及性能

以壳聚糖和环氧丙烷为原料合成了羟丙基壳聚糖,并以此为壳材,以胰岛素为芯材,制备了平均粒径为13．34μm的微球,并通过红外光谱、DSC和扫描电子显微镜对产物的结构进行了表征．结果发现,当搅拌速度为400r／min,HPCS的用量为叫（HPCS）-8％,交联剂戊二醛的体积分数Ф=0．25％（对液体石蜡）时,所制备的微球表面光滑、致密、平均粒径适中,且其包埋率较高,室温下稳定．     

Preparation and in vitro release properties of mercaptopurine drug-loaded magnetic microspheres

Magnetic Fe304 nanoparticles were synthesized by co-precipitation method and the mercaptopurine （MER） drug-loaded magnetic microspheres were obtained through emulsion cross-linking methods. The efficiency of this approach was evaluated in terms of drug loading content （DLC）, encapsulation efficiency （EE） and delivery properties in vitro, determined by high performance liquid chromatograph （HPLC）. The microspheres showed good DLC values of 11.8%, as well as good EE values of 79.4%. The in vitro drug release study was carried out in phosphate buffer solution （PBS） simulated body fluid, at 37 ~C with pH=7.4. The release profiles showed an initial fast release rate, which decreased as time progressed and about 84 % had been released after 48 h. The experimental results indicated that the prepared magnetic microspheres may be useful for potential applications of MER for magnetically targeted chemotherapy.     

聚合物纳米空心微球的制备及药物缓释性能研究

以二乙烯三胺和甲苯-2,4-二异氰酸酯为基本原料,在室温下通过反相细乳液界面聚合法制备了聚脲空心微球。研究了乳化剂、连续相、分散相和助稳定剂对反相细乳液稳定性和空心微球形貌的影响,并通过透射电子显微镜和红外光谱对其形貌和结构进行了分析。研究表明,当以司盘80为表面活性剂、甲酰胺为分散相、环己烷为连续相、Ag NO3为助稳定剂时,可制备出粒径在100 nm左右且具有明显空心结构的聚脲纳米微球,其微球囊壁厚度约为1 7 n m。以罗丹明B为模拟药物对纳米空心微球进行了药物装载及体外释放研究,研究结果表明空心微球具有较强的药物负载能力和良好的药物缓释性能,每克空心微球最大药物吸附量可达101 mg罗丹明B(即101 mg/g),体外连续释药时间能达14 h以上。     

无皂乳液聚合法制备PNIPAAm聚合物微球的温敏特性研究

采用无皂乳液聚合法制备了聚异丙基丙烯酰胺(PNIPAAm)温敏性聚合物微球,用TEM对微球的形貌进行了表征,并用紫外-可见光分光光度计对微球的最低临界溶解温度(LCST)进行了研究,讨论了共聚单体丙烯酰胺(Am)和交联剂N,N-亚甲基双丙烯酰胺(MBAM)加入量(质量分数)对微球LCST的影响。研究结果表明:随着MBAM加入量的增加,微球的粒径变大;当MBAM加入量超过15%后,会使聚合物微球尺寸过大而在水中的稳定性变差;随着单体Am和交联剂MBAM量的增加,微球LCST均升高,但同时其转变温度范围宽化,使其对温度的敏感性降低,当Am和MBAM的加入量占NIPAAm单体的质量分数分别为13%和10%时,LCST升高至40℃左右,有利于温敏性聚合物微球用于体内的药物缓释载体。     

HBsAg壳聚糖疫苗制备工艺及相关研究

研制以壳聚糖为载体的乙型肝炎疫苗,将乙肝病毒表面抗原疫苗包封在壳聚糖微球中,制备鼻腔免疫的新型微球疫苗,通过鼻腔注入免疫小鼠．普通乙肝疫苗由腹腔注入免疫小鼠．用ELISA方法检测血清中抗HBV的IgG,结果显示鼻腔及腹腔免疫效果无显著性差异．HBsAg壳聚糖微球疫苗的制备为鼻腔免疫乙型肝炎疫苗的开发提供了实验基础．     

Chitosan andβ-cyclodextrin Microspheres as Pulmonary Sustained Delivery Systems

Chitosan and a-cyclodextrin were used to prepare microspheres with theophylline for pulmonary delivery by spray drying method.The characteristics,mucociliotoxicity,permeation rate and drug release were studied.The drug entrapments of microspheres Ⅰ,Ⅱ and Ⅲ were from 35.70%to 21.09% and 13.33%.while yields and encapsulation efficiencies were higher than 45%and about 90%respectively.with smooth or wrinkled surface surfaces.FT-IR demonstrated theophylline had formed hydrogen bonds with chitosan and a-cyclodextrin.The mierospheres could effectively reduce the ciliotoxicity and easy to penetrate the memberine.The in vitro release of the microspheres was related to the ratio of drug/polymer and microspheres Ⅱ had a prolong release,providing the release of 72.00%in 12 h.The results suggestes that chitosan/ a-cyclodextrin microspheres Ⅱ are a promising carrier as sustained release for pulmonary delivery.     

Adsorption of BSA on Carbon-coated Fe_3O_4 Microspheres Activated with 1-ethyl-3-(3-dimethylaminopropyl)-Carbodiimide Hydrochloride

Carbon-coated Fe_3O_4( Fe_3O_4/C) microspheres activated with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride(EDC) were prepared, characterized and applied to adsorb bovine serum albumin(BSA). The prepared magnetic microspheres had spherical core-shell structure with a uniform and continuous carbon coating coupled with activation by EDC, and possessed superparamagnetic characteristics. The experimental results showed that the adsorption amount of BSA on the EDC-activated Fe_3O_4/C(Fe_3O_4/C-EDC) microspheres was higher than that on the Fe_3O_4/C microspheres. The maximum adsorption of BSA on Fe_3O_4/C-EDC microspheres occurred at pH 4.7, which was the isoelectric point of BSA. At low concentrations(below 1.0 M), salt had no noticeable effect on BSA adsorption. The BSA adsorption of Fe_3O_4/C-EDC microspheres had a better fit to the Langmuir model than the Freundlich isotherm and Temkin isotherm model, and the kinetic data were well described by the pseudo-second-order model. The adsorption equilibrium could be reached within 20 min. High desorption efficiency(97.6%) of BSA from Fe_3O_4/C-EDC microspheres was obtained with 0.5 M Na_2HPO_4(pH 9.4) as the desorbent.     

阿司匹林磁性壳聚糖微球的研制

利用壳聚糖的生物相容性,以Fe3O4作为磁性内核,以戊二醛作为交联剂,固载了阿司匹林,研制出阿司匹林磁性聚糖微球.对此磁性微球的大小、形态、含量和体外释药进行研究.结果表明,用此法研制的磁性微球成球性能好,无粘连,平均直径为5~10μm,载药率为0.922(W/W),包封率为82.4%.8 h内释药量为48.4%,24 h内释药量为80.8%,具有较好的缓释性.结论:阿司匹林磁性微球具有较高的包封率和显著的缓释阿司匹林作用.     

Preparation and Characterization in vitro of Sustained-release Captopril/Chitosan-gelatin Net-polymer Microspheres （Cap/CGNPMs）

The captopril/ Chitosan-gelatin net-polymer microspheres （ Gap/ CGNPMs ） were prepared using Chitosan （ CS ） and gelatin （ Gel ） by the methods of emulsification. A cross linked reagent alone or in combination with microcrystalline cellulose （ MCC ） was added in the process of preparation of microspheres to eliminate dose dumping and burst phenomenon of microspheres for the improvemeat of the therapeutic efficiency and the decrease of the side effects of captopril （ Cap ）. The results indicate that Cap/ CGNPMs have a spherical shape , smooth surface roorphology and integral inside structure and no adhesive phenomena and good roobility , and the size distribution is mairdy from 220 to 280 μm. Researches on the Cap release test in vitro demonstrate that Cap/ CGNPMs are of the role of retarding release of Cap compared with Cap ordinary tablets （COT）, embedding ratio （ER） , drug loading （ DL ）, and swelling ratio （ SR ）, and release behaviors of CGNPMS are influenced by process conditions of preparation such as experimental material ratio （EMR） , composition of cross linking reagents. Among these factors , the EMR（1/4）, CLR （ FOR ＋ TPP） and 0.75% microcrystulline cellulose （MCC） added to the microspheres are the optimal scheme to the preparation of Cap/CGNPMs. The Cap/CGNPMs have a good characteristic of sustained release of drug, and the process of emulsifieation and crossinking process is simple and stable. The CGNPMs is probable to be one of an ideal sustained release system for water-soluble drugs.     

新型耐温聚合物微球的封堵特性研究

采用扫描电子显微镜、激光粒度仪和微孔滤膜过滤实验研究了一种双交联结构新型耐温聚合物微球的形态、溶胀性能、耐温性能及封堵性能。结果表明,微球原始形态为表面较为光滑的圆球形,粒径主要分布在200~300 nm,微球在矿化度10 000 mg/L的水溶液中140 ℃下溶胀30 d后约溶胀了5倍。随着溶胀时间、溶胀温度和微球浓度的增加,微球对微孔滤膜的封堵能力逐渐增强,140 ℃下溶胀30 d的微球封堵效果最强;随着滤膜孔径的增大,微球封堵效果减弱。微球在140 ℃下溶胀30 d后依然具有良好的封堵性能,说明微球具有良好的耐温性。     

抗EGFR β环糊精/淀粉复合微球的制备及表征

构建抗EGFR免疫微球,以期为EGFR肿瘤分子靶点的早期诊断及免疫治疗奠定基础。采用反向微乳液法制备β环糊精/淀粉复合纳米球,并以环氧氯丙烷活化,交联FITC标记的抗EGFR抗体,得到了抗EGFR的荧光免疫β环糊精/淀粉球。考察了活化和交联的条件,并以交联率为指标,得到了单位复合纳米球交联的抗EGFR抗体量,并对产物进行了相关的特性研究。结果表明,由反向微乳液法制得的微球其粒径可达300 nm,活化的最优条件为:每0.1 g复合球添加环氧氯丙烷1.5 mL,NaOH浓度为2.0 mol/L,反应温度50℃,反应时间6 h。该活化条件下在37℃时,β环糊精/淀粉复合球交联的抗体量为2.7 mg/g,荧光显微镜下观察呈现较强的荧光。