茴三硫-聚乙二醇类固体分散体的研究

目的制备茴三硫固体分散体,提高其溶解度和溶出速率。方法以不同分子量不同比例的聚乙二醇为载体,以熔融法制备固体分散体,并进行体外溶出度研究和DSC扫描。结果茴三硫与聚乙二醇可形成低共熔物,并使溶出度大大增加,载体比例越大,药物溶出愈快。结论本试验所制茴三硫固体分散体能加速体外溶出,体外溶出与载体分子量无关,但与固体分散体载体比例有关。     

依普黄酮固体分散体的制备和溶出特性(英文)

目的:制备和鉴定依普黄酮固体分散体,测定它的体外溶出度。方法:用溶剂法制备依普黄酮固体分散体,用DSC,X衍射和红外光谱鉴定固体分散体,浆法测定它的溶出度。结果:由依普黄酮和聚维酮(1:8)组成的固体分散体,其体外溶出度是依普黄酮的6.15倍,DSC曲线,X衍射图谱和红外光谱均产生了明显变化。结论:依普黄酮被制成固体分散体能明显增加依普黄酮的体外溶出度。     

依折麦布固体分散体的制备及其体外溶出

目的制备难溶性药物依折麦布固体分散体,改善其溶出性质,为固体分散体技术提高难溶性药物溶出及生物利用度提供新的参考。方法以共聚维酮(polyvinyl pyrrolidone-vinyl acetate copolymer,PVP VA64)作为亲水性载体材料,采用溶剂挥发法制备不同处方的依折麦布固体分散体,并进行溶出度考察;通过红外光谱法、差式扫描量热法及X射线衍射法对依折麦布固体分散体进行表征与评价。结果依折麦布与PVP VA64的质量比为1∶10时,依折麦布在质量分数0.1%十二烷基硫酸钠醋酸盐缓冲液中30 min累积溶出接近100%,与物理混合物相比,显著提高了依折麦布固体分散体的体外溶出度,物态鉴别表明依折麦布以无定型状态存在于载体中。结论制备依折麦布PVP VA64固体分散体,可显著提高其体外溶出度。     

马来酸氟吡汀固体分散体的制备及体外溶出

目的:制备马来酸氟吡汀-PEG 6000固体分散体以加快药物的体外溶出速度。方法:以PEG 6000为药物载体,采用熔融法制备马来酸氟吡汀固体分散体,采用X-射线衍射法和差示扫描量热法(DSC)观察药物在载体中的存在状态。结果:马来酸氟吡汀以分子状态存在于固体分散体中;药物与载体的比例为1:4时,所制备的固体分散体具有最高的溶出度。结论:固体分散体能显著提高药物溶出度和溶出速率。     

瑞格列奈固体分散体的制备及体外溶出

目的制备瑞格列奈的固体分散体,提高瑞格列奈的体外溶出度。方法以聚乙二醇6000(polyethylene glycol 6000,PEG6000)作为载体,采用溶剂-熔融法制备不同处方的瑞格列奈固体分散体,进行溶出度考查。采用红外光谱、差示扫描量热(differential scanning calorimetry,DSC)与X-射线衍射(X-ray diffraction,XRD)对瑞格列奈固体分散体进行物相分析。结果与瑞格列奈原料和物理混合物相比,固体分散体可显著提高瑞格列奈的体外溶出度,物相鉴定表明,瑞格列奈大部分以无定形状态分散于PEG6000中,提高了药物的体外溶出度。结论制备瑞格列奈的PEG6000固体分散体能显著提高药物的体外溶出度,可满足速释制剂的要求。     

托伐普坦片的制备及体外溶出评价

目的探讨流化床干燥法制备固体分散体,以改善托伐普坦的溶出度。方法以乳糖为底物,水溶性材料羟丙纤维素为载体,采用流化床干燥法制备托伐普坦固体分散体,利用粉末X射线衍射对固体分散体进行表征,并研究其体外溶出度。结果X射线衍射结果显示,托伐普坦在流化床干燥过程中转变成了无定形;体外溶出结果显示,固体分散体样品的溶出度优于物理混合物样品。结论采用流化床干燥法制成固体分散体,可显著提高托伐普坦的体外溶出度。     

热熔挤出法制备槲皮素固体分散体

目的采用热熔挤出技术制备难溶性药物槲皮素的固体分散体,提高其溶出速率。方法以聚丙烯酸树脂(EudragitEPO)、聚维酮(PVP-K30)、共聚维酮(PVP-VA,Kollidon VA64)为亲水性载体材料,使用双螺杆热熔挤出机制备槲皮素固体分散体,通过体外溶出度测定、差示扫描量热法(DSC)、傅立叶红外光谱(FTIR)和X射线衍射法(XRD)来表征和评价所制备的固体分散体。结果制备的槲皮素固体分散体,与原料药相比,药物溶出得到显著提高,在人工胃液中3 min时处方槲皮素-EPO(1∶9)的药物溶出度可达到67%,处方槲皮素-木糖醇-PVPK30(1∶3∶6)的药物溶出度可达到65%,而在60 min时原料药溶出度不足10%。XRD图谱显示药物晶体衍射峰消失,DSC图谱显示药物熔点吸热峰消失,提示药物是以无定形态分散在载体材料中。结论热熔挤出技术可用于制备槲皮素固体分散体,使药物以无定型态高度分散在载体中,溶出度得到显著提高。     

盐酸胺碘酮固体分散体的制备及溶出度测定

目的制备盐酸胺碘酮固体分散体,测定其体外溶出度,同时与普通胶囊剂的体外溶出度比较。方法以聚乙二醇6000(PEG6000)为载体,溶剂熔融法制备盐酸胺碘酮固体分散体,用紫外分光光度法测定体外溶出度。结果盐酸胺碘酮固体分散体的体外溶出度比普通胶囊剂显著提高。结论成功制备了盐酸胺碘酮固体分散体。     

甘草黄酮固体分散体的制备及体外溶出性能考察

目的:制备甘草黄酮(LF)-聚乙烯吡咯烷酮K30(PVP K30)固体分散体,并对其进行表征及体外释药性能考察。方法:分别以聚乙烯吡咯烷酮K30(PVP K30)、聚乙二醇(PEG 4000、 PEG 6000)、泊洛沙姆188(F68)以及胶态二氧化硅(SiO2)为载体,采用溶剂法或溶剂熔融法制备固体分散体,考察其体外释药性能,并利用差式扫描量热仪(DSC)、傅里叶变换红外光谱(FT-IR)对固体分散体的结构特征进行表征。结果:以PVP K30为载体制备的固体分散体的体外溶出率优于其他载体制备的固体分散体,且以药物-载体比例1∶5时溶出度最佳。经DSC和FT-IR结果表明,固体分散体中的药物以无定形状态存在。结论:固体分散体技术能显著提高甘草黄酮的体外溶出度。     

姜黄素固体分散体的制备和溶出度考察

目的通过姜黄素固体分散体的制备,提高姜黄素的体外溶出度。方法采用溶剂法和熔融法制备固体分散体,考察不同载体的姜黄素固体分散体的性状及体外溶出度实验,筛选并优化处方和工艺。固体分散体的形成通过X-射线衍射及DSC分析证实。结果姜黄素与聚乙烯吡咯烷酮(polyvinyl pyrrolidone,PVP)-K29/32用溶剂法制备的固体分散体的体外溶出最好,最优处方中姜黄素与PVP-K29/32的质量比为1∶6,最优处方中姜黄素在溶出介质人工胃液中30 min累积溶出质量高达98%。结论制备成姜黄素固体分散体可以显著提高姜黄素的体外溶出度。     

Effects of ebselen on glutathione level in neurons exposed to arachidonic acid and 4-hydroxynonenal during simulated ischemia in vitro

Release of arachidonic acid (AA) is a neurotoxic mechanism of oxidative nature in trauma and ischemia. We studied ebselen effects on AA and 4-hydroxynonenal toxicity in rat cortical neurons in simulated ischemia in vitro by assessing cell viability and glutathione concentration. Ebselen normalized neuronal viability diminished by AA and 4-hydroxynonenal and increased glutathione level in normoxia and ischemia. AA elevated the glutathione level by 52 and 14% and 4-hydroxynonenal by 63 and 39% in normoxia and ischemia, respectively. Ebselen augmented the effect of AA in normoxia and diminished it in ischemia. Effect of 4-hydroxynonenal was similarly modulated by ebselen.     

替硝唑固体分散体的制备及其体外释放特性研究

目的:利用固体分散技术制备替硝唑固体分散体,增加替硝唑溶解度和溶出速度。方法:以聚乙二醇(PEG)为载体材料,采用溶剂-熔融法制成固体分散体,测定表观溶解度,进行体外溶出试验,并采用差示扫描量热(DSC)法鉴别药物在固体分散体中的存在状态。结果:替硝唑的溶出度和表观溶解度随PEG的比例不同而不同,且溶出度随载体用量增加而增加。固体分散体的DSC曲线中替硝唑药物的特征熔融峰消失。结论:所制得的固体分散体能明显提高替硝唑的溶出度和表观溶解度。     

Ebselen对自由基诱发的皮层神经元和皮层线粒体脂质过氧化损伤的保护作用

观察了ebselen对超氧阴离子O^·-₂和羟自由基·OH诱发的体外培养大鼠皮层神经元乳酸脱氢酶(lactic dehydrogenase,LDH)释放,和TBARS(thiobarbituric acid reactive substance)含量升高及制备的皮层线粒体TBARS含量升高的影响。结果表明:超氧阴离子和羟自由基引起了培养神经元和线粒体明显的损伤。浓度在5～50μmol·L^-1之间,ebselen能剂量依赖性地抑制LDH释放和TBARS含量的增加,对线粒体的TBARS含量升高也有显著的抑制作用。但浓度为0.2～50μmol·L^-1时,药物无直接清除超氧阴离子和羟自由基的活性。因此,ebselen对氧自由基诱发的神经元脂质过氧化损伤有拮抗作用,这种作用与直接清除自由基无关。     

Analysis of a Nanocrystalline Polymer Dispersion of Ebselen Using Solid-State NMR, Raman Microscopy, and Powder X-ray Diffraction

Purpose

Nanocrystalline drug-polymer dispersions are of significant interest in pharmaceutical delivery. The purpose of this work is to demonstrate the applicability of methods based on two-dimensional (2D) and multinuclear solid-state NMR (SSNMR) to a novel nanocrystalline pharmaceutical dispersion of ebselen with polyvinylpyrrolidone-vinyl acetate (PVP-VA), after initial characterization with other techniques.

Methods

A nanocrystalline dispersion of ebselen with PVP-VA was prepared and characterized by powder X-ray diffraction (PXRD), confocal Raman microscopy and mapping, and differential scanning calorimetry (DSC), and then subjected to detailed 1D and 2D SSNMR analysis involving ¹H, ¹³C, and ⁷⁷Se isotopes and ¹H spin diffusion.

Results

PXRD was used to show that dispersion contains nanocrystalline ebselen in the 35?C60?nm size range. Confocal Raman microscopy and spectral mapping were able to detect regions where short-range interactions may occur between ebselen and PVP-VA. Spin diffusion effects were analyzed using 2D SSNMR experiments and are able to directly detect interactions between ebselen and the surrounding PVP-VA.

Conclusions

The methods used here, particularly the 2D SSNMR methods based on spin diffusion, provided detailed structural information about a nanocrystalline polymer dispersion of ebselen, and should be useful in other studies of these types of materials.     

间尼索地平固体分散体的研制

目的:将难溶性药物间尼索地平制备成固体分散体,以增加其溶解度及体外溶出度。方法:以泊洛沙姆为载体,共沉淀法制备间尼索地平固体分散体。采用差示扫描量热分析(DSC)方法鉴别药物在载体中的存在状态,并进行溶解度和体外溶出度研究。结果:DSC显示间尼索地平与泊洛沙姆形成了低共熔物,间尼索地平原料药及其与泊洛沙姆不同比例的固体分散体(1∶3、1∶5、1∶7)的溶解度分别为0.89、4.50、15.35、23.03mg·L-1,120min时的累积溶出百分率分别为26.80%、38.57%、41.38%、45.92%,固体分散体的溶出度高于同比例的物理混合物。结论:以泊洛沙姆为载体制备间尼索地平固体分散体,可增加药物的体外溶出度和溶解度。     

微管蛋白抑制剂SUD-35固体分散体的制备、鉴定及初步体外药效学研究

目的将难溶性微管蛋白抑制剂SUD-35制备成固体分散体,以增加其溶解度及溶出速率。方法以聚乙二醇6000为载体,溶剂-熔融法制备SUD-35固体分散体。采用差示扫描量热分析与X-射线衍射观察药物在载体中的存在状态,并进行溶解度和体外溶出度研究。采用MTT法对SUD-35固体分散体对小鼠白血病L1210细胞药效进行测定。结果 SUD-35固体分散体中SUD-35的溶解度和溶出速率相对原料药和物理混合物均有明显提高,差示扫描量热分析与X-射线衍射结果显示SUD-35以无定型状态存在于固体分散体中,细胞药效结果显示SUD-35固体分散体对小鼠白血病L1210细胞增殖抑制率强于SUD-35纯药。结论聚乙二醇6000为载体制备SUD-35固体分散体,可显著提高SUD-35的溶解度及溶出速率。     

Ebselen: prospective therapy for cerebral ischaemia

Stroke occurs due to haemorrhage or occlusive injury and results in ischaemia and reperfusion injury. A variety of destructive mechanisms are involved including oxygen radical generation, calcium overload, cytotoxicity and apoptosis as well as the generation of inflammatory mediators. Ebselen, 2-phenyl-1, 2-benzisoselenazol-3(2H)-one (PZ 51, DR3305), is a mimic of GSH peroxidase which also reacts with peroxynitrite and can inhibit enzymes such as lipoxygenases, NO synthases, NADPH oxidase, protein kinase C and H(+)/K(+)-ATPase. Ebselen is in a late stage of development for the treatment of stroke. The molecular actions of ebselen contribute to its anti-inflammatory and anti-oxidant properties, which have been demonstrated in a variety of in vivo models. Numerous in vitro experiments using isolated LDL, liposomes, microsomes, isolated cells and organs have established that ebselen protects against oxidative challenge. Unlike many inorganic and aliphatic selenium compounds, ebselen has low toxicity as metabolism of the compound does not liberate the selenium moiety, which remains within the ring structure. Subsequent metabolism involves methylation, glucuronidation and hydroxylation. Experimental studies in rats and dogs have revealed that ebselen is able to inhibit both vasospasm and tissue damage in stroke models, which correlates with its inhibitory effects on oxidative processes. Results from randomised, placebo-controlled, double-blind clinical studies on the neurological consequences of acute ischaemic stroke, subarachnoid haemorrhage and acute middle cerebral artery occlusion, have revealed that ebselen significantly enhances outcome in patients who have experienced occlusive cerebral ischaemia of limited duration. The benefit achieved with ebselen is closely related to the rapidity with which the treatment is initiated, following the onset of the stroke attack. Safety and tolerability are good and no adverse effects have become apparent. Ebselen is currently at the pre-registration stage for subarachnoid haemorrhage and stroke in Japan.     

In vitro evaluation and pharmacokinetics in dogs of solid dispersion pellets containing Silybum marianum extract prepared by fluid-bed coating

The solid dispersion of a poorly water-soluble Silybum marianum extract (SME) was prepared by a one-step fluid-bed coating technique depositing onto non-pareil pellets. In vitro evaluation indicated that this technique was highly efficient and reproducible producing pellets with acceptable appearance, flowability, friability, uniformity of drug content and enhanced dissolution. Physical characterization by DSC, powder X-ray diffractometry and FT-IR suggested the formation of a solid dispersion and possible interaction between PVP and the flavonolignans. Stress testing showed that the drug content and dissolution profiles of the SME solid dispersion pellets were sensitive to heat and humidity, while they are not affected under accelerated and long-term testing conditions. The relative bioavailability of solid dispersion pellets in dogs based on quantification of silibinin was about five-fold that of the SME suspension confirming enhanced oral bioavailability. It was concluded that the solid dispersion pellets prepared by fluid-bed coating showed favorable in vitro characteristics and enhanced oral bioavailability.