三维有序大孔淀粉材料改善达比加群酯的溶出行为

目的 制备三维有序大孔淀粉材料（three-dimensional ordered macroporous starch material,3DOMS）,改善难溶性药物达比加群酯（dabigatran etexilate,DBET）的溶出度。方法 通过硬模板法制备3DOMS;溶剂挥发法进行载药;借助X射线衍射法、差示扫描量热法和傅里叶红外光谱法表征考察药物存在状态;溶出度实验验证DBET溶出度改善情况。结果 3DOMS具有三维有序的纳米级连通孔道结构,借助其纳米级空间抑制效应能够有效抑制难溶性药物的结晶度,载药样品（DBET-3DOMS）中DBET以无定形态存在,体外溶出度实验表明药物溶出效果明显改善。结论 3DOMS能够有效改善DBET的溶出,作为生物可降解材料在改善难溶性药物水溶性方面具有较大潜力。     

三维有序大孔壳聚糖/尼莫地平固体分散体的研究

目的制备孔径为470nm的三雏有序大孔壳聚糖／尼莫地平的固体分散体,研究其释药特点、稳定性和药动学。方法利用溶剂蒸发法制备固体分散体,通过药物释放试验考察固体分散体在模拟胃肠液介质中的释放行为;通过含量测定、X-射线衍射和溶出试验检查固体分散体的稳定性;大鼠分别给予自制固体分散体和市售片粉末,测定血药浓度。结果固体分散体在pH6.8的介质中的溶出度明显比pH1.2和pH4.5介质中高,在梯度pH介质中的释药曲线类似阶梯型;结晶度和溶出度在考察时间内基本无变化;自制固体分散体的AUC0.12h是市售制剂的1.91倍,具有长效作用。结论自制固体分散体稳定性良好,能够提高尼莫地平的大鼠口服生物利用度。     

三维适形放疗加羟基喜树碱治疗原发性单结节型肝癌近期疗效观察

目的:观察三维适形放射联合羟基喜树碱治疗原发性单结节型肝癌近期疗效及耐受性.方法:19例肝癌均采用三维适形放疗,≥90%的等剂量线包绕PTV,5～8 GY/次,1次/日,3次/周,总剂量55～64 GY/3～4周;放疗开始同时给予羟基喜树碱5 mg静脉滴注,连用21天,休息两周后改为羟基喜树碱10 mg/d,连用5天,21天为1个周期,共3～4周期.结果:19例患者均顺利完成治疗计划,完全缓解2例,部分缓解15例,总有效率89.5%(17/19);主要不良反应为骨髓抑制,均能耐受.结论:三维适形放疗加羟基喜树碱治疗原发性单结节型肝癌近期疗效好,局部控制率高,不良反应低,患者耐受性好.     

9-硝基喜树碱胶囊溶出过程的研究

目的建立9-硝基喜树碱(9-NC)胶囊的溶出度测定方法。方法考察了不同溶出介质、转速和温度对溶出试验的影响;选择HPLC法测定9-NC的含量,同时对该测定方法的准确度、精密度、重复性和线性范围进行了评价,测定了同一规格3批样品的溶出曲线。结果 0.05～8μg.mL-19-NC与峰面积的线性关系良好(r=0.9999),平均回收率为99.32%,RSD=0.93%;3批样品在45 min内溶出百分率均大于90%,释放行为符合威布尔分布模型与多项式模型中的四次多项式模型。结论将9-NC释放行为作为控制的指标,能保证其胶囊的质量。     

羟喜树碱固体分散体的制备及体外溶出

目的:制备了羟喜树碱的固体分散体,并考察其体外溶出速率.方法:选择聚乙二醇6000作为载体,用熔融法、溶剂熔融法制备羟喜树碱固体分散体,进行其体外溶出的研究.结果:熔融法制备羟喜树碱-PEG 6000的固体分散体溶出速率明显提高.结论:PEG 6000是提高羟喜树碱溶出速率的理想载体.     

抑制P-糖蛋白的羟基喜树碱纳米混悬剂的制剂学评价

采用微沉淀-高压匀质法制备具有高过饱和溶出水平、高渗透性和物理稳定的口服羟基喜树碱纳米混悬剂(hydroxycamptothecin nanosuspensions,HCPT-Nano),并对其粒径及分布、zeta电位、粒子形态、物理存在状态、贮存稳定性及过饱和溶出水平等制剂学性质进行了评价。结果表明,HCPT-Nano的粒径小于300 nm且分布均匀,粒子多呈棒状或块状,药物以结晶形式存在,能长期维持较高的过饱和溶出水平。因此,结合P糖蛋白(P-glycoprotein,P-gp)的抑制剂环孢素A(cyclosporin,CsA)的加入,为提高HCPT的口服生物利用度提供了可能性。     

介孔二氧化硅和中空介孔二氧化硅载体用于提高难溶性药物溶出度的比较

目的研究介孔二氧化硅(mesoporous silica nanoparticles,MSN)和中空介孔二氧化硅(hollow mesoporous silica nanoparticles,HMSN)两种载体对提高难溶性药物缬沙坦(valsartan,VAL)和尼莫地平(nimodipine,NMP)的载药量以及改善药物溶出度作用的比较。方法采用溶剂挥干法制备VAL-MSN、VAL-HMSN、NMP-MSN和NMP-HMSN四种固体分散体,以紫外分光光度法测定样品的载药量。采用X射线衍射法表征药物的存在状态。以溶出度为评价指标,对原料药、无定型药物以及载药体系的溶出速率进行了比较。结果 VAL-HMSN和NMP-HMSN的载药量分别为(34.76±1.36)%和(38.30±1.38)%,而VAL-MSN和NMP-MSN的载药量分别为(23.54±1.72)%和(22.93±1.08)%。X射线衍射实验表明药物在载体中以非晶体状态存在。溶出实验结果显示无定型药物的溶出度最低,HMSN和MSN载药体系的溶出度均比原料药有所提高。结论 HMSN和MSN相比,HMSN载药体系的载药量更高,但溶出度较MSN载药体系低。     

羟基喜树碱纳米脂质载体的制备及体外释放

采用“熔融乳化-高压均质法”制备以PEG40硬脂酸酯、PEG100硬脂酸酯修饰的纳米脂质载体PEG40-NLC和PEG100-NLC，并考察释放装置、NLC中脂质材料用量及释放介质流速对体外释放的影响。结果表明，PEG40-NLC和PEG100-NLC在桨-反向动态透析法和流通池-动态透析法中的释放曲线相似，而在转篮-动态透析法中的释放曲线与前二种装置的释放曲线均有显著性差异。随着NLC脂质材料用量增大，释放过程中药物扩散作用增强。对流通池法，释放介质流速增大，药物的释放加快。     

聚乙二醇修饰的羟基喜树碱纳米脂质载体的制备及其小鼠组织分布

本研究采用熔融乳化-高压均质法制备了聚乙二醇(PEG)修饰的羟基喜树碱(HCPT)纳米脂质载体(HCPT-PEG-NLC)及非修饰的羟基喜树碱纳米脂质载体(HCPT-NLC)，并考察了其形态、粒径及包封率。测定了HCPT注射液、HCPT-PEG-NLC及HCPT-NLC 3种制剂经小鼠尾静脉注射后在血浆、心、肝、脾、肺、肾及卵巢等主要组织的浓度，评价了HCPT-PEG-NLC及HCPT-NLC在各组织的靶向性效果。透射电镜下观察，HCPT-PEG-NLC及HCPT-NLC呈球形；测得平均粒径分别为(88.6±22.5)和(127.2±43.4)nm；包封率分别为(90.51±3.29)%和(84.37±2.81)%。经小鼠尾静脉注射后，HCPT-PEG-NLC及HCPT-NLC在多数取样时间点的血药浓度较HCPT注射液有所提高，HCPT在各组织中的消除半衰期明显延长。HCPT-NLC蓄集于网状内皮系统(RES)，在肝、脾的相对摄取率(R_e)和峰浓度比(C_e)明显高于HCPT-PEG-NLC。HCPT-PEG-NLC延长了药物在血浆中的滞留时间，提高了生物利用度，MRT及AUC_{0-24 h}分别为注射液的19.80和17.02倍，并且与HCPT-NLC比较显著降低了RES的吞噬作用，在肺部表现出明显的靶向作用(R_e及C_e分别为14.51，41.35)。综上，HCPT-PEG-NLC可延长HCPT的体内循环时间，呈现明显的肺靶向性，有望作为HCPT肺癌治疗的理想载体。     

醒脑再造丸大蜜丸与水蜜丸的体外溶出度比较

目的 建立醒脑再造丸溶出度测定方法,以总黄酮成分为指标比较醒脑再造丸大蜜丸和水蜜丸两种不同剂型的体外溶出差异.方法 应用溶出度测定法第二法桨法,测定大蜜丸和水蜜丸在4个不同溶出介质的累积溶出率,利用紫外分光光度法测定醒脑再造丸两种剂型中总黄酮的含量,比较两种不同制剂的溶出行为.结果水蜜丸在4个溶出介质的累积溶出率分别为51.57%、71.97%、24.73%、50.78%;大蜜丸在4个溶出介质中累积溶出率分别为41.94%、69.82%、16.10%、48.52%.从差异因子和相似因子分析,两种制剂中相同成分的溶出曲线无相似性.结论 本文建立了醒脑再造丸溶出度测定方法,两种制剂中水蜜丸累积溶出率快. 说明在体外溶出方面,水蜜丸这种中药剂型有利于机体对药物的充分吸收,生物利用度高.     

介孔碳(CMK-3)载体用于提高非诺贝特溶出速率及物理稳定性的研究

目的以制备的介孔碳(CMK-3)为载体载入非诺贝特制备纳米药物分散体系,以期提高非诺贝特的溶出速率和纳米分散药物的稳定性。方法采用吸附平衡法将模型药物非诺贝特载入到碳载体中,应用扫描电子显微镜(SEM)来表征制备载体的形貌,透射电子显微镜(TEM)和氮吸附曲线表征载体的内部孔道结构,差示扫描量热(DSC)和X射线衍射(XRD)研究药物在载体中的存在状态,采取溶出度测定方法研究所制备的载药体系的药物溶出速度,并测定其长期稳定性。结果药物已载入碳载体的纳米孔道中,且药物粒子的高度分散和晶型的转变,显著提高了难溶性药物非诺贝特的溶出速率,并且碳载体的刚性结构有效阻止了分散药物粒子的再聚集,物理稳定性大大提高。结论制备的非诺贝特-CMK-3载药体系,为提高难溶性药物的生物利用度以及解决纳米分散药物的物理稳定性等问题,提供了一种可能。     

Incorporation of indomethacin nanoparticles into 3-D ordered macroporous silica for enhanced dissolution and reduced gastric irritancy

In the present study, we exploited for the first time the potential of 3-D ordered macroporous (3DOM) silica as matrix for drug nanoparticles, in order to obtain proper control over drug particle size in the sub-micrometer range, enhance the dissolution rate, and reduce gastric damage. 3DOM silica matrix with 3-D spherical pores of 200 nm was successfully created and then loaded with IMC nanoparticles at various drug-silica ratios. A rapid release profile for IMC nanoparticle formulations was achieved in comparison with microsized IMC and a commercial capsule, which could be attributed to both increase in the specific surface area and decrease in the crystallinity of IMC, as well as the hydrophilic surface and the interconnected pore networks of 3DOM silica. Reduced gastric damage of IMC was demonstrated, and the protective effect may arise from the reduction in drug particle size as well as encapsulation effect of 3DOM silica.     

The use of ordered mixtures for improving the dissolution rate of low solubility compounds

The dissolution rate of micronized griseofulvin has been investigated, both for the agglomerated raw material and the material formulated as an ordered mixture, by means of the USP XX paddle method. During the experiments, which were performed at sink condition and constant temperature, the effects of adding a surfactant and of agitation were tested. The ordered mixture with sodium chloride gave a fast dissolution rate, practically independent of the test parameters. Micronized griseofulvin alone gave dissolution profiles that were improved by adding polysorbate 80 and by increased agitation, but the dissolution rates obtained were much lower than those for the ordered mixture. It was concluded that the rate limiting step in the dissolution of griseofulvin as the raw material is the penetration of the dissolution medium into the agglomerates. With an ordered mixture, these agglomerates were deaggregated during the mixing process, producing a system in which the entire external surface area of the primary particles was exposed to the dissolution medium. This conclusion was supported by calculation of the contact surface areas taking part in the dissolution process for the systems tested. The procedure developed in this study could be applied to preformulation work where a cohesive, low solubility drug of hydrophobic nature is to be formulated.     

有序介孔硅胶提高难溶性药物白藜芦醇的溶出速率

本研究的目的是制备有序介孔硅胶并考察其作为难溶性药物载体的体外药物释放特点。以十六烷基三甲基溴化铵为模板合成了有序介孔硅胶, 以白藜芦醇为模型药物, 采用扫描电镜、透射电镜、N₂吸附-脱附、X-射线衍射和红外光谱对载药前后的有序介孔硅胶进行表征, 并考察药物体外释放行为。结果表明, 合成的有序介孔硅胶比表面积大、粒度均匀, 具有有序六方孔道结构, 载药后药物以无定形态或分子态存在, 释放速率明显提高。有序介孔硅胶有望成为新型的难溶性药物载体。     

Use of the liquisolid compact technique for improvement of the dissolution rate of valsartan

The aim of this study was to improve the dissolution rate of the poorly soluble drug valsartan by delivering the drug as a liquisolid compact. Liquisolid compacts were prepared using propylene glycol as solvent, Avicel PH102 as carrier, and Aerosil 200 as the coating material. The crystallinity of the newly formulated drug and the interaction between excipients was examined by X-ray powder diffraction and Fourier-transform infrared spectroscopy, respectively. The dissolution studies for the liquisolid formulation and the marketed product were carried out at different pH values. The results showed no change in the crystallinity of the drug and no interaction between excipients. The dissolution efficiency of valsartan at 15 min was increased from 4.02% for plain drug and 13.58% for marketed product to 29.47% for the liquisolid formulation. The increase in the dissolution rate was also found to be significant compared to the marketed product at lower pH values, simulating the gastric environment where valsartan is largely absorbed. The liquisolid technique appears to be a promising approach for improving the dissolution of poorly soluble drugs like valsartan.     

管状介孔硅用于提高西洛他唑的溶出速率及对其物理稳定性的影响

目的以合成不同于传统球形介孔硅的管状硅(mesoporous silica tube,MST)为载体,制备西洛他唑(cilostazol,CLT)固体分散体系(CLT-MST),提高难溶性药物CLT的溶出速率和物理稳定性。方法采用多壁纳米碳管(carbon nanotube,CNT)为硬模板,以表面活性剂十六烷基三甲基溴化铵(cetyltrimethyl ammonium bromide,CTAB)为辅助模板制备MST,应用扫描电子显微镜(scanning electron microscope,SEM)、透射电子显微镜(transmission electron microscope,TEM)和比表面积分析仪表征MST外在形貌和内部孔道特征。采用挥干载药的方法,将CLT载入制备的MST中,并测定所制备的固体分散体系的药物溶出度,以差示扫描量热仪(differential scanning calorimetry,DSC)和X射线衍射仪(X ray diffraction,XRD)分析药物在载体中的存在状态。最后对介孔硅固体分散体系进行稳定性试验。结果所制备CLT-MST在1 h时累计溶出度达到82%,且储存6个月后CLTMST的DSC和XRD表征图谱均没有显著变化。结论 MST可使难溶性药物CLT高度分散,能够改善CLT的溶出速率以及保持CLT的物理稳定性。     

羟基喜树碱/羟丙基-β-环糊精包合作用研究

目的:研究羟基喜树碱/羟丙基-β-环糊精的包合,寻找改善羟基喜树碱溶解度的新方法.方法:研磨法制备包合物,以差示热分析法和红外光谱法对包合物进行鉴定,采用紫外分光光度法、相溶解度法、计算机模拟计算法验证羟基喜树碱/羟丙基-β-环糊精包合物的形成.结果:羟基喜树碱能够与羟丙基-β-环糊精形成物质的量比为1∶1的包合物,且溶解度由原来的0.22μg·mL-1增至包合后的38.2μg·mL-1.结论:羟丙基-β-环糊精可提高羟基喜树碱的溶解度.     

Co-precipitates of lumefantrine-Eudragit E PO for dissolution improvement

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Benzyl ether-linked glucuronide derivative of 10-hydroxycamptothecin designed for selective camptothecin-based anticancer therapy

A beta-glucuronidase-activated prodrug approach was applied to 10-hydroxycamptothecin, a Camptotheca alkaloid with promising antitumor activity but poor water solubility. We synthesized a glucuronide prodrug of 10-hydroxycamptothecin ( 7) in which glucuronic acid is connected via a self-immolative 3-nitrobenzyl ether linker to the 10-OH group of 10-hydroxycamptothecin. Compound 7 was 80 times more soluble than 10-hydroxycamptothecin in aqueous solution at pH 4.0 and was stable in human plasma. Prodrug 7 was 10- to 15-fold less toxic than the parent drug to four human tumor cell lines. In the presence of beta-glucuronidase, prodrug 7 could be activated to elicit similar cytotoxicity to the parent drug in tumor cells. Enzyme kinetic studies showed that Escherichia coli beta-glucuronidase had a quite low K m of 0.18 microM for compound 7 and exhibited 520 times higher catalytic efficiency for 7 than for 6 (a glucuronide prodrug of 9-aminocamptothecin). Molecular modeling studies predicted that compound 7 would have a higher binding affinity to human beta-glucuronidase than compound 6. Prodrug 7 may be useful for selective cancer chemotherapy by a prodrug monotherapy (PMT) or antibody-directed enzyme prodrug therapy (ADEPT) strategy.     

固体分散技术提高枸橼酸莫沙必利片溶出度的研究

目的考察固体分散技术对枸橼酸莫沙必利片的体外溶出度的影响。方法以聚维酮K30为载体制备枸橼酸莫沙必利片固体分散体,紫外分光光度法对其体外溶出度进行测定。结果聚维酮K30-枸橼酸莫沙必利比例大于2∶1(w/w)时所得枸橼酸莫沙必利片5 min累积溶出量接近100%,而市售品溶出缓慢,5 min累积溶出量约为50%,30min累积溶出量约为90%。结论采用固体分散技术制备的枸橼酸莫沙必利片能显著提高枸橼酸莫沙必利的溶出速率。