The bioavailability of ingested 26Al-labelled aluminium and aluminium compounds in the rat

The fractional uptake of ingested aluminium and aluminium compounds (aluminium citrate, aluminium nitrate, aluminium chloride, aluminium sulphate, aluminium hydroxide, aluminium oxide, aluminium metal, powdered aluminium pot electrolyte, acidic sodium aluminium phosphate (SALP), basic sodium aluminium phosphate (Kasal), sodium aluminium silicate and FD&C red 40 aluminium lake) from the gastro-intestinal tract of adult female rats was measured. This was determined by comparing retained body burden of ²⁶Al at seven days post-admistration of an i.v. injection of ²⁶Al-labelled aluminium citrate with that retained following the gastric admistration of ²⁶Al-labelled test compounds as either solutions or suspended solid. The calculated percentage uptake of ²⁶Al for all the aluminium solutions was similar: aluminium citrate 0.08%, aluminium chloride 0.05%, aluminium nitrate 0.05% and aluminium sulphate 0.21%. The uptake of ²⁶Al administered as insoluble particulates was lower: 0.03% for aluminium hydroxide; 0.02% for aluminium oxide; 0.04% for powdered pot electrolyte; 0.12% for sodium aluminium silicate; and 0.09% for FD&C red 40 aluminium lake. For aluminium metal, SALP and Kasal the amount of ²⁶Al present in the rats was insufficient to determine uptake and was less than 0.03%. The results produced for aluminium citrate, aluminium hydroxide and aluminium sulphate are close to those published for man.     

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。     

Comparative pharmacokinetics and tissue distribution of cryptotanshinone,tanshinone IIA,dihydrotanshinone I,and tanshinone I after oral administration of pure tanshinones and liposoluble extract of Salvia miltiorrhiza to rats

Salvia miltiorrhiza is one of the most commonly used traditional Chinese medicines in the treatment of cardiovascular and cerebrovascular diseases. Cryptotanshinone (CTS), tanshinone IIA (Tan IIA), dihydrotanshinone I (diTan I), and tanshinone I (Tan I) are the main active compounds in the liposoluble extract of Salvia miltiorrhiza. The differences in the pharmacokinetic and tissue distribution behaviors of the four tanshinones after oral administration of the liposoluble extract of Salvia miltiorrhiza and pure compounds are not clear. This study aims to compare the pharmacokinetics and tissue distribution of the four tanshinones after oral administration of pure tanshinone monomers and the liposoluble extract of Salvia miltiorrhiza. An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) analysis method was developed for the determination of the four tanshinones. The results showed that the AUC and C_max of tanshinones in rats receiving the extract of Salvia miltiorrhiza were significantly increased compared with those receiving the pure tanshinones. In the tissue distribution experiments, the AUC of the four tanshinones in the extract was much greater than the AUC of the monomers in the lung, heart, kidney, liver, and brain, and the coexisting constituents particularly promoted the distribution of tanshinones into tissues that the drug cannot sufficiently penetrate. These findings suggested that the coexisting constituents in the liposoluble extract of Salvia miltiorrhiza play an important role in the alteration of plasma concentration and tissue distribution of the four tanshinones. Understanding these differences could be of significance for the development and application of Salvia miltiorrhiza extract and tanshinone components.     

Novel protease inhibitor-loaded Nanoparticle-in-Microparticle Delivery System leads to a dramatic improvement of the oral pharmacokinetics in dogs

With the advent of the Highly Active Antiretroviral Therapy, the morbidity and the mortality associated to HIV have been considerably reduced. However, 35–40 million people bear the infection worldwide. One of the main causes of therapeutic failure is the frequent administration of several antiretrovirals that results in low patient compliance and treatment cessation. In this work, we have developed an innovative Nanoparticle-in-Microparticle Delivery System (NiMDS) comprised of pure drug nanocrystals of the potent protease inhibitor indinavir free base (used as poorly water-soluble model protease inhibitor) produced by nanoprecipitation that were encapsulated within mucoadhesive polymeric microparticles. Pure drug nanoparticles and microparticles were thoroughly characterized by diverse complementary techniques. NiMDSs displayed an encapsulation efficiency of approximately 100% and a drug loading capacity of up to 43% w/w. In addition, mucoadhesiveness assays ex vivo conducted with bovine gut showed that film-coated microparticles were retained for more than 6 h. Finally, pharmacokinetics studies in mongrel dogs showed a dramatic 47- and 95-fold increase of the drug oral bioavailability and half-life, respectively, with respect to the free unprocessed drug. These results support the outstanding performance of this platform to reduce the dose and the frequency of administration of protease inhibitors, a crucial step to overcome the current patient-incompliant therapy.     

蒙花苷磷脂复合物的制备及其药动学评价

目的 制备蒙花苷磷脂复合物，研究其药动学性质。方法 溶剂挥发法制备蒙花苷磷脂复合物，以复合率为评价指标，通过正交试验优化制备工艺。SD大鼠灌胃给予蒙花苷磷脂复合物，HPLC测定蒙花苷的血药浓度。结果 采用优化后的磷脂复合物制备工艺，复合率接近100%。X射线衍射结果表明蒙花苷以无定型状态存在于磷脂复合物中，在水和正辛醇中的表观溶解度显著增大。药动学结果显示，蒙花苷磷脂复合物的t_max，C_max，AUC_0-t等参数与蒙花苷原料药相比具有显著性差异，口服吸收生物利用度提高1.11倍。结论 磷脂复合物改善了蒙花苷的溶解性质，口服吸收生物利用度得到明显提高。     

Oral Dispersible System: A New Approach in Drug Delivery System

Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day''s more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form.     

阿立哌唑自乳化释药系统的制备与质量评价

目的 制备阿立哌唑自乳化释药系统（ARP-SEDDSs）以提高药物的口服生物利用度。方法 HPLC法检测ARP在不同的油、表面活性剂和助表面活性剂中的溶解度,根据溶解度确定处方组成;采用伪三元相图筛选SEDDSs的处方比例;通过动态光散射、透射电镜、稀释稳定性和体外溶出对ARP-SEDDSs进行表征;大鼠分别ig给予自制ARP-SEDDSs和ARP混悬液（20 mg·kg^-1）后,HPLC法进行药动学研究,考察大鼠ig ARP-SEDDSs的生物利用度。结果 以油酸作为油相,以聚乙二醇15-羟基硬脂酸酯和异丙醇作为表面活性剂和助表面活性剂,优化得到ARP-SEDDSs处方为油酸-聚乙二醇15-羟基硬脂酸酯-异丙醇为2.0∶5.6∶2.4,载药量为10 mg·g^-1;ARP-SEDDSs经水稀释后可快速形成微乳,在透射电镜下可观察到微乳呈类球形,经动态光散射仪检测其平均粒径为（54.6±2.3）nm,聚合物分散性指数（PDI）为0.201±0.011,Zeta电位（-13.5±0.4）mV;ARP-SEDDSs在pH 6.8磷酸盐缓冲液中10 min的药物溶出度接近100%,远高于阿立哌唑口崩片（约10%）。大鼠体内药动学研究表明,与ARP混悬液相比,ARP-SEDDSs相对生物利用度为248.8%。结论 将ARP制备成自乳化释药系统,有助于药物快速溶出,显著提高了ARP的口服生物利用度。