难溶性中药成分在过饱和体系下晶体成核和生长行为研究

目的研究难溶性中药成分在过饱和体系中的晶体成核和生长行为,为难溶性中药成分过饱和给药系统的设计奠定基础。方法通过反溶剂法制备载药过饱和体系,选择紫外-可见光谱法监测晶体成核和晶体生长过程,分别测定6种成分在较低过饱和度(S=5)和较高过饱和度(S=20)时的晶体成核诱导时间(tind)和晶体生长速度,利用偏振光显微镜(PLMC)、X射线衍射(XRD)、差示扫描量热仪(DSC)对沉淀进行表征。结果穿心莲内酯、延胡索乙素、丹皮酚、银杏内酯B、高饱和度的水飞蓟宾与姜黄素的成核诱导时间tind1 h,低过饱和度的水飞蓟宾与姜黄素的成核诱导时间tind1 h;穿心莲内酯与延胡索乙素在晶体生长过程中表现出负斜率,而水飞蓟宾、丹皮酚、姜黄素与银杏内酯B在则表现出正斜率。结论穿心莲内酯与延胡索乙素属于快速成核-快速晶体生长分子(I类);丹皮酚、银杏内酯B、较高过饱和度的水飞蓟宾与姜黄素属于快速成核-缓慢晶体生长分子(II类)、较低过饱和度的水飞蓟宾与姜黄素属于缓慢成核-缓慢晶体生长分子(IV类)。     

含功能性油的水飞蓟宾超饱和自纳米乳的制备与体外评价

目的制备含功能性油的水飞蓟宾超饱和自纳米乳(SLB-S-SNEDDS),并对其进行表征及体外评价研究,以提高难溶性药物水飞蓟宾的生物利用度。方法铁氢化钾还原力与1,1-二苯基-2-苦肼基(DPPH)自由基清除实验筛选功能性油脂;伪三元相图考察乳化剂乳化能力;测定粒径、多分散指数(PDI)、Zeta电位等考察混合油相比例与载药量;相容性与溶出度实验筛选促过饱和物质并考察其质量浓度;从外观、粒径分布、自乳化效率、形态学等方面表征SLB-S-SNEDDS,并进行溶出度、抗氧化能力、细胞毒性等体外评价。结果所得SLB-S-SNEDDS处方为(1)小麦胚芽油/Capryol 90-Cremophor ELP-Transcutol HP与(2)沙棘籽油/Capryol 90-Cremophor ELP-Transcutol HP,1 g基质(包含0.043 g小麦胚芽油或沙棘籽油、0.387 g Capryol 90、0.380 g Cremophor ELP、0.190 g Transcutol HP),水飞蓟宾的添加量为各组分平衡溶解度之和的20%,Soluplus的添加量为上述总质量的0.1%。小麦胚芽油、沙棘籽油体系分别为淡黄色、亮黄色透明状均一液体,2种体系自乳化分散后均呈近球形白色扁平乳滴,粒径约为50 nm,乳化时间均为65 s。与药物原料及SLB-SNEDDS相比,SLB-S-SNEDDS中水飞蓟宾的累积溶出率8h内均维持在85%～110%,表明该体系能够显著提高药物的溶出度。SLB-S-SNEDDS与铁氰化钾反应后的吸光度(A值0.452～0.782,0.488～0.765)以及DPPH自由基清除率(39.09%～96.02%,30.54%～89.20%)均高于相应质量浓度下水飞蓟宾原料的A值与清除率(0.411～0.760,22.89%～63.21%),表明2种处方体系均能提高水飞蓟宾的抗氧化能力。细胞毒性实验结果显示,在5、10μmol/L药物浓度下,水飞蓟宾原料组、水飞蓟宾S-SNEDDS组及其相应的空白S-SNEDDS组细胞生存率均90%,说明SLB-S-SNEDDS及其所用辅料对人克隆结肠腺癌细胞(Caco-2)毒性较小、安全性较好。结论制备的含功能性油SLB-S-SNEDDS在提高水飞蓟宾累积溶出率的同时,增强了其抗氧化能力,为将超饱和自纳米乳(S-SNEDDS)用于改善难溶性药物水溶性及其生物活性提供有益参考。     

Effect of Soluplus on the supersaturation and absorption of tacrolimus formulated as inclusion complex with dimethyl-β-cyclodextrin

The application of tacrolimus (FK506) is hampered by its poor solubility and dissolution, which can be promoted by the use of inclusion complex. However, in supersaturated environment, crystallization of the drug inclusion complex may occur, leading to reduced absorption in vivo. In this study, Soluplus, an amphiphilic copolymer of polyvinyl caprolactam, polyvinyl acetate and polyethylene glycol, was used to improve the supersaturated stability and absorption of FK506. Using dimethyl-β-cyclodextrin (DM-β-CD), the inclusion complex (FK506-CD) was prepared, which showed favorable dissolution profiles. But in supersaturated condition, the drug concentration was rapidly decreased, with 10.64?±?0.69?μg/ml of FK506 at 12?h. Ternary complex (FK506-SCD) containing Soluplus contributed steadier drug concentration. The FK506-SCD with 1.2% Soluplus best promoted the supersaturated stability of the inclusion complex, with 62.90?±?3.34?μg/ml of FK506 at 12?h. Soluplus also reduced the crystallization and degradation of FK506 in the stress test. In the single-pass intestinal perfusion test, the absorption of FK506 in the ileum and colon was significantly increased. Pharmacokinetic results showed that the bioavailability of FK506-SCD was 2.34-fold that of FK506-CD. Our data suggested that Soluplus had an excellent capability in improving the supersaturated stability and in vivo absorption of FK506 inclusion complex.     

促过饱和物质对多西他赛自乳化系统体外释药特性的影响

 目的 研究促过饱和物质对多西他赛自乳化系统（DTX-SEDDS）释药特性的影响。方法 测定DTX-SEDDS的体外溶出度,并考查不同的促过饱和物质,促过饱和物质的不同用量,不同的投药量以及不同的释放介质对DTX-SEDDS体外释药特性的影响。 结果 不同的促过饱和物质如羟丙基甲基纤维素(HPMC)、十二烷基磺酸钠（SDS）、聚维酮（PVPK30）、Avicel RC591中,HPMC的促溶和稳定作用最强;不同厂家同黏度的HPMC对药物溶出影响差异不显著,同浓度不同黏度的HPMC对药物溶出影响有显著性差异,低黏度的好于高黏度HPMC;HPMC的不同用量对DTX-SEDDS体外释药有一定影响;当低黏度HPMC的用量为1%～8%,累积溶出百分率无显著差异,当高黏度HPMC的用量≤0.5%或≥8%时药物溶出明显减少;不同介质对药物溶出影响无显著性差异。推荐自乳化处方中选择加入1%～8%的低黏度HPMC（型号：山东50,山东100或上海K100）效果较好。结论 过饱和物质HPMC可以明显提高DTX-SEDDS的溶出和稳定性,同时可减少自乳化油的用量,可提高自乳化制剂的临床安全性。     

联苯双酯过饱和自微乳释药系统的体内外评价

 目的 研究联苯双酯过饱和自微乳(BDD-S-SMEDDS的体外自乳化能力和体内药动学。方法 采用动态光散射法测定BDD-S-SMEDDS乳化后的粒径分布和Zeta电位;考察不同的促过饱和物质及不同用量对BDD-S-SMEDDS体外析晶的影响,并测定BDD-S-SMEDDS的体外溶出度;测定Beagle犬体内血药浓度,与市售滴丸相比,考察BDD-S-SMEDDS的体内药动学。结果 聚乙烯吡咯烷酮K30（PVP的促过饱和效果较好,其用量为0.5％～2％时均有较好的药物抑晶作用;BDD-S-SMEDDS加入水稀释后迅速乳化形成微乳,平均粒径为(38.40±0.28 nm,Zeta电位为(-8.00±0.99 mV;体外溶出度10 min时达到80％以上,比市售滴丸溶出显著提高;体内药动学数据表明,BDD-S-SMEDDS软胶囊达峰时间t_max提前,最大血药浓度ρ_max(143.29±52.91 μg·L-1是市售滴丸的2.6倍,AUC为市售滴丸的1.92倍。结论 BDD-S-SMEDDS体系中促过饱和物质PVPK30的加入,可以提高稳定性,减少表面活性剂的用量,并且显著提高BDD的体外溶出和体内吸收。     

穿心莲内酯过饱和自微乳化释药系统的制备及体外评价

目的:优选穿心莲内酯过饱和自微乳化释药系统的处方工艺,以提高穿心莲内酯的溶解度及生物利用度。方法:通过溶解度试验及伪三元相图的工艺初步筛选后,采用单纯形网格法,以粒径、多分散指数和乳化时间为指标,确定穿心莲内酯自微乳的处方;以析晶情况、粒径、多分散指数、乳化时间以及穿心莲内酯的溶出度为考察指标筛选最佳促过饱和抑制剂。结果:穿心莲内酯过饱和自微乳处方为油酸乙酯-(聚山梨酯-80)-聚乙二醇400-羟丙基甲基纤维素K4M(20∶35∶45∶1)。穿心莲过饱和自微乳乳化后的平均粒径(29.26±0.56)nm,多分散指数0.19±0.02,Zeta电位(-10.23±2.34)mV,乳化时间(62.39±2.03)s,1 h累积溶出度高达91%。结论:加入羟丙基甲基纤维素K4M后可明显抑制穿心莲内酯自微乳液的析晶时间,增加自微乳的稳定性;相较于普通自微乳可明显提高穿心莲内酯的体外溶出度,进而提高该成分的生物利用度。     

Bioactivity Evaluation of Biphasic Hydroxyapatite Bone Substitutes Immersed and Grown with Supersaturated Calcium Phosphate Solution

Recently, the frequency of use of bone substitute materials for the purpose of bone augmentation has increased in implant treatment, but bone formation with bone substitute materials alone is limited. Calcification of bone in the body progresses as Ca²⁺, H₂PO^4-, and HPO₄^2- in the body form hydroxyapatite (HA) crystals. In this study, therefore, we prepared a biphasic bone substitute with biological activity to promote bone formation by inducing precipitation and growth of HA crystals on the surface of a bone substitute and evaluated it. Biphasic bone substitute granules were prepared by immersing HA granules in a supersaturated calcium phosphate solution prepared by mixing five medical infusion solutions, the precipitate was analyzed, and the biological activities of biphasic HA granules were evaluated in vitro and in vivo. As a result, the precipitated calcium phosphate crystals were identified as low crystalline HA. On the surface of the HA granules, low-crystalline HA grew markedly as needle-shaped crystals and significantly promoted cell proliferation and bone differentiation. In animal experiments, biphasic HA granules had a significantly higher bone mineral density, new bone volume ratio, and new bone area ratio. Therefore, it suggests that biphasic hydroxyapatite is a useful bone substitute for bone augmentation in dental implant treatment.     

阿瑞匹坦三元超饱和固体分散体的制备及性能考察

目的：为了提高难溶性药物阿瑞匹坦(Aprepitant,APR)的溶解度,解决其酸中溶出、碱中结晶沉淀的问题,选择不同功能的聚合物载体,采用热熔挤出技术制备三元固体分散体,并对其进行性能考察;方法：采用溶剂-熔融法制备二元固体分散体,以溶出度和溶出速度为指标,筛选具有增溶功能的载体材料。通过介质转移法考察各聚合物在不同浓度的药物溶液中的抑晶性能,筛选出最佳的沉淀抑制剂。确定药载比,将APR、溶出促进剂及沉淀抑制剂以不同比例混合,采用热熔挤出技术制备三元固体分散体,以溶出度和抑晶时间为指标,优选出三元固体分散体处方。经XRD确认药物在载体中的存在状态,考察该三元固体分散体在模拟肠液中的动态溶解度和加速条件下的物理稳定性。结果：亲水性聚合物PVP K30制备的二元固体分散体溶出速度快,增溶效果佳,肠溶性聚合物HPMCAS显示出优越的抑晶作用,延长了APR的过饱和点,质量比为1:1:3(APR:PVP K30:HPMCAS)的三元固体分散体在酸中迅速完全释放(120min溶出95%),相对于原料药显著提高了溶出度和溶出速率,当介质pH转为6.8后,三元固体分散体完全释放并在6h内维持溶液处于高过饱和的稳定状态,药物以无定形形式存在于载体基质中,同时能在加速条件下保持至少三个月的无定形状态。结论：基于不同聚合物的理化特性,本研究制备的三元固体分散体通过协调溶出速率和结晶抑制效果,不仅显著提高APR的溶解度,并能解决APR在胃中溶出、肠中沉淀析晶的问题,具有良好的溶出特性。     

木犀草素纳米混悬剂的制备及其体外肠吸收研究

目的 通过制备木犀草素纳米混悬剂（luteolin nano-suspension,LNS）,以提高木犀草素的水溶性、溶出速度和小肠吸收。方法 采用微沉淀-高压匀质法制备LNS,以粒径、稳定性、多分散指数（polydispersity index,PDI）、ζ电位为考察指标,通过单因素筛选法对处方进行了初步优化。采用动态光散射法、差示扫描量热法（differential scanning calorimetry,DSC）和X射线粉末衍射（X-ray powder diffraction,XRPD）对纳米混悬剂进行表征,再采用桨法考察纳米混悬剂的体外溶出度,通过大鼠外翻肠模型实验,考察十二指肠、空肠、回肠和结肠不同部位的肠段对药物的吸收情况。结果 以维生素E聚乙二醇琥珀酸酯（D-α-tocopherol polyethylene glycol 1000 succinate,TPGS）作为稳定剂,稳定剂与药物质量比为1∶1时,可以制备得到粒径为210 nm左右,分散性和储存稳定性良好的LNS;其ζ电位在（−16.30±0.78）mV,透射电子显微镜图显示,LNS呈均匀分散的球形或椭圆形纳米粒;DSC和XRPD研究结果表明,制备成LNS后,没有改变木犀草素的结晶状态;而体外溶出实验结果表明,LNS可以明显提高木犀草素的过饱和溶出度;外翻肠实验结果证实,LNS虽然不能改变木犀草素在小肠中的吸收部位,但可以大幅度提高木犀草素的吸收速率和吸收量。结论 所制备的LNS可以显著提高药物的水溶性、溶出速度和小肠吸收,用于木犀草素口服给药的潜在剂型。     

PRIMARY STRUCTURE OF THE ACTIVE TRYPTIC FRAGMENTS OF HUMAN AND MONKEY SALIVARY ANIONIC PROLINE-RICH PROTEINS

The primary structures of the four human salivary anionic proline-rich proteins and an analogous protein from the saliva of a monkey (Macaca arctoides) have been further investigated. These proteins possess the unusual property of inhibiting crystal growth of calcium phosphate salts, and it has been proposed that they play an important role in the mouth, by preventing precipitation of calcium phosphate salts from the supersaturated saliva. The tryptic fragments responsible for this activity have been isolated from all five proteins and their complete amino acid sequences determined and compared. These active fragments have been unequivocally identified as the amino-terminal segment in all five proteins. The structures of the four human fragments are identical except for the presence of Asn at residue 4 in PRP-1 and -3 instead of Asp found in PRP-2 and -4. Comparison of the 30 residue human fragments with the monkey fragment shows 18 residues to be identical in these peptides, providing that residue 1 of the monkey fragment is aligned with residue 3 of the human proteins. These studies constitute the next step in determining the mechanism of action of these unusual proteins, and in determining their minimum chain length required for inhibitory activity.