丹皮酚缓释微球的制备及体内外相关性研究

制备具有固体分散结构的丹皮酚缓释微球,并考察其体内外相关性。采用乳化溶剂扩散法制备丹皮酚缓释微球,考察微球的外观、载药量、包封率及体外释放行为。并以丹皮酚原料药为对照,根据大鼠的体内药物动力学试验结果,考察自制微球的体内外相关性。药物在37℃蒸馏水中12 h释放达到85%以上,大鼠体内的药动学实验表明,制得的丹皮酚缓释微球的体外释放累积百分数与体内吸收分数相关系数较好（r=0.977 5）,生物利用度是丹皮酚原料药的136.81%。该方法较适用于难溶性药物制备缓释微球。     

头孢拉定缓释片的研制

采用粉末直接压片法,以体外释放度为指标,通过调节缓释骨架材料丙烯酸树脂Ⅱ号用量对处方进行优化,制备头孢拉定缓释片剂,并考察剂型、体外释药试验方法、压片压力,释放介质等对体外累积释放率的影响．结果显示制得的缓释片处方设计合理,工艺重现性好,释药行为符合Weihull方程,体外释放度符合2010版药典规定．     

盐酸二甲双胍缓释片的制备工艺及体外释放度研究

制备盐酸二甲双胍缓释片，并建立测定其释放度的方法。采用羟丙甲纤维素（HPMC）为缓释材料制备盐酸二甲双胍缓释片，用紫外分光光度法测定其释放度。考察了填充剂的种类、粘合剂的种类对本品释放度的影响，井采用正交试验进行处方优化。依据最优处方制备了三批缓释片。与盐酸二甲双胍普通片比较，本品有显著的缓释效果，其体外释放度曲线12g内符合Higuchi方程。     

Preparation and properties of gelatin-chitosan/montmorillonite drug-loaded microspheres

A kind of slow release drug-loaded microspheres were prepared with gelatin, chitosan and montmorillonite(MMT) by an emulsification/chemical cross-linking method using glutaraldehyde as cross-linking agent and acyclovir as model drug. The microspheres were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM), respectively. The morphology, drug content, encapsulation efficiency and drug-release behavior were investigated with different MMT content...     

白藜芦醇凝胶骨架缓释片的制备及体外释放机制研究

以白藜芦醇(Resveratrol,RES)为模型药物,羟丙基甲基纤维素(HPMC)为骨架材料,制备白藜芦醇凝胶骨架缓释片,考察凝胶骨架缓释片的处方工艺和体外释放条件对其释放的影响。采用分光光度法测定缓释片的体外释放度,通过零级、一级和Higuchi模型探讨缓释片的释放机制。结果表明:最优处方制备的缓释片符合一级释放方程,压片压力、释放介质pH值和搅拌转速对白藜芦醇凝胶骨架缓释片释放均有一定影响。以HPMC4000为骨架材料,可以制备出具有理想缓释效果的白藜芦醇凝胶骨架缓释片。     

聚碳酸酯纳米药物的制备与性能

采用可生物降解高分子材料链接或包埋抗癌药物制备高分子纳米或微米药物,不仅可以提高药物的抗癌功效而且能减小药物对正常组织的毒副作用.以9 苯基 2,4,8,10 四氧螺\[5,5\]十一烷 3 酮与2,2 二甲基二亚甲基合成的羟基化的碳酸酯共聚物P(PTC co DTC)为载体,将肿瘤靶向基团叶酸通过化学反应键连在聚碳酸酯的侧链,从而制备肿瘤靶向性高分子载体,并进行了傅立叶红外光谱、核磁共振氢谱、紫外 可见光谱等结构表征.再将靶向高分子载体与5 氟尿嘧啶复合,采用高压电场喷雾法与透析法分别制得两种肿瘤靶向聚碳酸酯纳米抗癌药物,并初步研究了纳米抗癌药物的体外药物控制释放性能.研究结果表明碳酸酯纳米药物具有较好的药物释放性能,且高压电场喷雾法制备的纳米药物比透析法制备的纳米药物释放药物速率快.     

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.     

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.     

尼索地平缓释微丸的制备及其体外释放度的考察

研制了尼索地平缓释微丸并进行体外释放度考察。通过正交试验确定最佳处方和工艺,并进行质量考察。确定了以乙基纤维素、羟丙甲纤维素为阻滞剂,聚乙二醇6000为增塑剂的最佳薄膜衣处方。尼索地平缓释微丸可缓慢释放12h以上。制备缓释微丸的工艺简单,易于控制和操作,且释放度标准符合规定。     

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.     

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.     

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.     

Preparation and characterization of chitosan microsphere loading bovine serum albumin

To optimize the preparation process of chitosan microspheres and study its loading capacity, chitosan microsphere was prepared by crosslinking with glutaraldehyde, and bovine serum albumin (BSA) was absorbed onto chitosan microsphere. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FITR), TA instruments and zeta potentiometer analyzer were used to characterize the parameters with respect to size, thermal characters, morphology, and zeta potential of the microspheres. The loading capability and in vitro release tests were carried out. The results showed that chitosan microsphere with particle size less than 10 μm and positively charged (+25.97±0.56 mV) can be obtained under the aldehyde group to amino group ratio at 1:1. A loading capacity of BSA at 28.63±0.15 g/100 g with corresponding loading efficiency at 72.01±1.44% was obtained for chitosan microsphere. In vitro test revealed a burst release followed by sustained-release profile.     

柿叶总黄酮缓释微丸累积释药率的测定

采用紫外-可见分光光度法测定了柿叶总黄酮缓释微丸在人工胃液和磷酸盐缓冲液(pH=6.8)中的累积释药率,并分别对其释药模型进行拟合.结果显示缓释微丸在磷酸盐缓冲液中12h的累积释药率为83.22%,释药模型符合Higuchi方程;在人工胃液中12h的累积释药率为55.42%,释药模型为Higuchi方程.相较于人工胃液,柿叶总黄酮缓释微丸在磷酸盐缓冲液中具有良好的释药性能.     

固体分散技术制备葛根素亲水凝胶缓释片

采用固体分散技术制备葛根素亲水凝胶缓释片。先采用单因素实验制备葛根素固体分散体,然后通过正交试验考察HPMC的K4M型和K15M型的质量比m(K4M):m(K15M)(A),HPMC的质量分数(B),淀粉与乳糖质量比m(淀粉):m(乳糖)(C),淀粉与乳糖合计的质量分数(D)4个因素对葛根素亲水凝胶缓释片的影响。得到葛根素固体分散体的最佳制备工艺:以PEG4000为载体,药物与载体的质量比为1:6;葛根素亲水凝胶缓释片的最佳制备工艺为:HPMC的K4M型和K15M型质量比m(K4M):m(K15M)=1:2,HPMC的质量分数为片重的30%,淀粉与乳糖的质量比m(淀粉):m(乳糖)=1:3,淀粉与乳糖合计的质量分数为片重的40%。该缓释片处方合理,工艺可行,达到缓释的预期目的。     

Chitosan and <Emphasis Type="Italic">β</Emphasis>-cyclodextrin microspheres as pulmonary sustained delivery systems

Chitosan and β-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. The microspheres possessed low tap densities （0.34-0.48 g/cm^3）, appropriate diameters （3.35-3.94 μm） and theoretical aerodynamics diameters （2.20-3.04 μm）. SEM images showed the microspheres were spherical with smooth or wrinkled surface surfaces. FT-IR demonstrated theophylline had formed hydrogen bonds with chitosan and fl-cyclodextrin. The microspheres 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/β-cyclodextrin microspheres Ⅱ are a promising carrier as sustained release for pulmonary delivery.     

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%.     

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.     

Preparation and Characterization of Superparamagnetic Fe_3O_4/CNTs Nanocomposites Dual-drug Carrier

Fe_3O_4/carbon nanotubes(Fe_3O_4/CNTs) nanocomposites were prepared by polylol hightemperature decomposition of the precursor ferric chloride and CNTs in liquid triethylene glycol.After surface modification with hexanediamine,folate was covalently linked to the amine group of magnetic Fe_3O_4/CNTs nanocomposites.The products were characterized by Fourier-transform infrared spectroscopy,transmission electron microscopy,and vibrating sample magnetometry.Then Fe_3O_4/CNTs were used as a dual-drug carrier to co-delivery of the hydrophilic drug epirubicin hydrochloride and hydrophobic drug paclitaxel.The results indicated that the Fe_3O_4/CNTs had a favorable release property for epirubicin and paclitaxel,and thus had potential application in tumor-targeted combination chemotherapy.     

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.