Solid Lipid Microparticles (SLM) Containing Juniper Oil as Anti-Acne Topical Carriers: Preliminary Studies

Solid lipid microparticles (SLM) were used as carriers of juniper oil and proposed for the topical treatment of acne vulgare. The formulations were obtained by the o/w emulsification method. Compritol and Precirol were employed as lipidic materials. Emulsions containing 1.5% (w/w) of lipophilic phase (lipid and oil) and two different lipid to oil ratios (1:1 and 2:1) were prepared. Blank particles were also prepared, as a comparison. The SLM were characterized in terms of encapsulation efficiency, size, and morphology. The particle size stability in aqueous dispersions was monitored over one month. Evaporation of volatile compounds of oil from microparticles by weight loss was investigated. The qualitative composition of Juniper oil before and after the encapsulation process was determined by gas chromatography (GC) and gas chromatography/mass spectrum (GC/MS) analyses. The antimicrobial activity of the oil encapsulated into the lipid microparticles against P. acnes was studied as contact time assay and compared to the activity of the oil not encapsulated. The emulsification method here described was a good technique for the encapsulation of essential oils. Percentage yields of production and encapsulation efficiencies were higher for Compritol preparations than for these prepared using Precirol. All preparations were characterized by similar particle size distributions (dvs about 3–4 µm) regardless of lipid type and lipid to oil ratios. Microscopy observations showed that the microparticles in aqueous dispersions had almost spherical shape, independently from their composition. The scanning electron microscopy (SEM) analyses showed that when the particles were dried, they had an irregular shape and a rough surface. The SLM dispersions based on Compritol revealed particle size stability over the investigated period of 30 days. In contrast, an increase of the mean dimensions in the preparations containing Precirol was observed. A low loss of volatile oil compounds owing to evaporation from dry particles was found in all preparations. This indicated that the microparticles were able to substantially maintain the oil loaded inside their lipidic structure, reducing its volatility. Some modifications of composition were found in the oil encapsulated in SLM with respect to the juniper oil raw material, but these modifications did not decrease the antibacterial activity of the oil. The SLM here described are promising carriers for the development of anti-acne topical formulations containing Juniper oil.     

Effect of Glass Transition Temperature on the Stability of Lyophilized Formulations Containing a Chimeric Therapeutic Monoclonal Antibody

Purpose. The purpose of this study is to highlight the importance of knowing the glass transition temperature, T_g, of a lyophilized amorphous solid composed primarily of a sugar and a protein in the interpretation of accelerated stability data. Methods. Glass transition temperatures were measured using DSC and dielectric relaxation spectroscopy. Aggregation of protein in the solid state was monitored using size-exclusion chromatography. Results. Sucrose formulation (T_g ~ 59°C) when stored at 60°C was found to undergo significant aggregation, while the trehalose formulation (T_g ~ 80°C) was stable at 60°C. The instability observed with sucrose formulation at 60°C can be attributed to its T_g (~59°C) being close to the testing temperature. Increase in the protein/sugar ratio was found to increase the T_gs of the formulations containing sucrose or trehalose, but to different degrees. Conclusions. Since the formulations exist in glassy state during their shelf-life, accelerated stability data generated in the glassy state (40°C) is perhaps a better predictor of the relative stability of formulations than the data generated at a higher temperature (60°C) where one formulation is in the glassy state while the other is near or above its T_g.     

氮酮对鬼臼毒素固体脂质纳米粒透皮性的影响

目的 考察氮酮对鬼臼毒素固体脂质纳米粒透皮性的影响。方法 以大鼠腹部皮肤为屏障，考察氮酮浓度（体积比）对鬼臼毒素固体脂质纳米粒表现透皮系数的影响。结果 当氯酮浓度分别为0，1％，2％，3％。4％，5％，6％时，鬼臼毒素脂质纳誊粒的表观透皮系数（x10^5）分别为24．82，53．05，55．14，43．92，20．57，25．86，23，30。结论 在有效浓度范围内，氮酮可增加鬼臼毒索固体脂质纳米粒的透皮吸收，含不同浓度氮酮的鬼臼毒素固体脂质纳米粒的透皮能力有差异。     

维甲酸固体脂质纳米粒中主药的含量及包封率测定

目的:建立测定维甲酸固体脂质纳米粒(atRA-SLNs)中主药含量及包封率的方法。方法:采用高效液相色谱法测定atRA-SLNs中主药含量,并采用超速离心法分离该制剂中的游离药物,测定其包封率。结果:维甲酸进样量的线性范围为0·016~0·128μg(r=0·9999,n=7);平均回收率为99·36%(RSD=0·37%);3批样品的包封率均大于96·0%。结论:该方法准确可靠、快速简单,可用于该制剂的含量及包封率测定。     

Physical Stability of an Amorphous Sugar Matrix Dried From Methanol as an Amorphous Solid Dispersion Carrier and the Influence of Heat Treatment

An amorphous sugar matrix, after drying from an organic solvent, was investigated for use as a method for dispersing hydrophobic drugs (solid dispersion). However, the amorphous sugar, originally contained in the organic solvent, had a significantly low glass transition temperature (T_g), thus rendering it physically unstable. In this study, we examined the physicochemical properties of a sugar in a dried matrix and in an organic solvent, using α-maltose and methanol as a representative sugar and organic solvent. The apparent molar volume of α-maltose was ∼30% smaller in methanol than in water. The methanol-originated amorphous α-maltose exhibited a much greater degree of hydrogen bonding than the water-originated one. Considering these findings, we conclude that the α-maltose maintained its compact conformation in the dried state and consequently caused the markedly low T_g. Second, it was found that heating under appropriate conditions resulted in an increase in the T_g of the methanol-originated amorphous α-maltose as well as a decrease in the level of hydrogen bonding. The aqueous dissolution of 2 model hydrophobic drugs (indomethacin and ibuprofen) from the solid dispersion was also improved as the result of the heat treatment, whereas, to the contrary, the dissolution of another model drug (curcumin) was lowered.     

长春新碱固体脂质纳米粒的制备工艺优化

目的制备长春新碱固体脂质纳米粒(VCR-SLN)并优化其处方组成和制备工艺。方法单因素考察筛选载体、稳定剂及制备工艺,用正交试验进行优化,以包封率、载药量和粒径为指标,筛选最佳处方和制备工艺,并对在优化条件下制备的VCR-SLN进行质量评价。结果以单硬酸酯甘油酯为载体,大豆卵磷脂、泊洛沙姆188为乳化剂,采用复乳-溶剂扩散法制备得VCR-SLN,其平均粒径为156.3 nm,包封率为55.12%,载药量为3.09%。结论复乳-溶剂扩散法适用于制备VCR-SLN。     

18α-甘草酸固体脂质纳米粒抗大鼠急性肝损伤作用研究

目的 研究18α-甘草酸固体脂质纳米粒（18α-glycyrrhizic acid solid lipid nanoparticles,18α-GL-SLN）的抗大鼠急性肝损伤作用。方法 用CCl4致大鼠急性肝损伤,以生化指标和病理变化评价18α-GL-SLN的抗肝损伤作用。结果 与模型组比较,18α-GL-SLN各剂量组和18α-GL组ALT、AST、TBil、γ-GT、ALP水平明显降低,差异有统计学意义（P〈0.05）,提示对大鼠急性肝损伤均有一定的治疗作用,尤其是18α-GL-SLN中、高剂量组,效果优于18α-GL组（P〈0.05）;病理切片显示各给药组肝组织损伤明显减轻。结论 18α-GL-SLN有抗CCl4致大鼠急性肝损伤作用,并且其作用优于18α-GL。     

三七叶总皂苷对高脂血症大鼠血脂、肝功能及脂质过氧化的影响

目的 探讨三七叶总皂苷对实验性高脂血症大鼠血脂水平、肝功能及脂质过氧化的影响。方法 采用SD大鼠灌胃脂肪乳剂建立高脂血症模型,给予三七叶总皂苷4周,检测血清中总胆固醇（TC）、甘油三酯（TG）、高密度脂蛋白胆固醇（HDL-c）、低密度脂蛋白胆固醇（LDL-c）、丙氨酸氨基转移酶（ALT）、天冬氨酸氨基转移酶（AST）;在给予三七叶总皂苷10周后,检测血清和肝组织中超氧化物歧化酶（SOD）、丙二醛（MDA）。结果 三七叶总皂苷可降低大鼠血清TC、LDL-c、ALT、AST,升高HDL-c/TC比值;同时能提高血清和肝组织中SOD的活力,降低MDA水平。结论 三七叶总皂苷可以调节高脂血症模型大鼠血脂水平和肝功能,同时具有一定的抵抗脂质过氧化作用,提示三七叶总皂苷对预防高胆固醇血症具有积极作用。     

主动靶向脂质体的相变温度与靶细胞摄取的相关性研究

分别采用二硬脂酰磷脂酰胆碱(DSPC)、氢化大豆磷脂(HSPC)、二棕榈酰磷脂酰胆碱(DPPC)和二肉豆蔻酰磷脂酰胆碱(DMPC)为载体,制备了NGR肽(Asn-Gly-Arg)修饰的主动靶向脂质体,并用其负载香豆素-6.结果表明,4种脂质体的粒径为120～160 nm,粒度分布均匀,ζ电位接近中性,包封率均在95％以上.差示扫描量热分析(DSC)表明,4种脂质体的相变温度(Tm)值由高至低分别为DSPC脂质体＞HSPC脂质体＞DPPC脂质体＞DMPC脂质体.以CD13高表达的HT1080细胞为模型,采用流式细胞仪、激光共聚焦显微镜观察评价脂质体的入胞效果.结果显示,脂质体的入胞效率与Tm值呈正相关.     

一氧化碳对血脂,脂质过氧化物含量及动脉粥样硬化影响的研究

健康雄性SD大鼠吸入62.6、375、750mg/m~3 CO,中、高浓度CO使大鼠血COHb、血清TG、LDL-CH及LPO含量增高,750mg/m~3 CO使主动脉内膜出现内皮下水肿、内皮细胞间裂隙及细胞核扭曲、变形等超微结构改变。提示:脂质过氧化、脂质代谢及主动脉内膜超微结构的改变,是CO所致动脉粥样硬化的重要病因学因素。     

Effect of Gelation on the Chemical Stability and Conformation of Leuprolide

Purpose. The purpose of this study was to characterize the conformation, aggregation, and stability of leuprolide on gelation. Methods. Infrared spectra (FTIR) of leuprolide solutions and gels were collected in water, propylene glycol (PG), dimethyl sulfoxide (DMSO), and trifluoroethanol (TFE). Leuprolide solution and gel stability data were obtained by SEC and RP-HPLC. Results. Leuprolide was induced to gel with increasing peptide concentration, introduction of salts, and gentle agitation. Leuprolide dissolved in water (400 mg/ml) demonstrated FTIR spectra consisting of two major bands of equal intensity at 1615 cm^–1 and 1630 cm^–1, similar to inter- and intra-molecular -sheet structure in proteins. When samples were gently agitated for 24 hours at 25°C, the formulation was observed to change from a viscous liquid to an opaque gel with a concomitant shift in infrared spectra from the equal intensity bands to mostly 1630 cm^–1, indicating a shift to a preferred -sheet structure. Incubation of leuprolide with 20–200 mM salts at 25°C and 37°C also produced gels ranging from clear to cloudy and stringy white precipitates. The gel and precipitate were marked by a shift of the predominant p-sheet band to 1630 cm^–1 and 1615 cm^–1, respectively. Leuprolide was also observed to gel and/or precipitate in mixtures of water, PG or TFE, but not in DMSO. Conclusions. Birefringence was noted in many of the firmer gels. Both solutions and gels demonstrated minimal dimer or trimer formation, with no larger order aggregates detected. The chemical stability profile of gelled leuprolide was similar to that of the non-gelled water formulation by RP-HPLC.     

The Effect of Size on Uptake of Orally Administered Latex Microparticles in the Small Intestine and Transport to Mesenteric Lymph Nodes

Purpose. The present study examines the relationship between size and particle transit across the mucosal barrier of the gastrointestinal tract to other sites of the body. The extent of particle uptake with increasing size, the tissue distribution and cut-off points for 2–20µm particles is investigated. Methods. An established fluorescent latex particle-young adult rat model is used and particle numbers in small intestine and mesenteric lymph nodes, 0.5 h post administration, counted by fluorescence microscopy in bulk tissue specimens and cryosections. Results. Bulk tissue analysis provides evidence for the presence of particles of all sizes in the Peyer's patch regions, but only for 2 µm particles in the nodal tissues. Microscopy establishes uptake of both 2 and 6 µm particles in most intestinal and nodal tissue sites and compartments. By contrast, uptake of the larger particles is much reduced. Conclusions. Although more of the smaller (2 µm) particles are taken up, particularly by epithelial tissues, the 6µm size appears more efficient in terms of volume translocated to lymph nodes. This could have implications in the therapeutic use of particles for drug and vaccine delivery and for radiation safety.     

蜕皮甾酮对大鼠局灶性脑缺血脂质过氧化损伤的影响

目的观察蜕皮甾酮（EDS）对大鼠局灶性脑缺血脂质过氧化损伤的影响。方法应用大脑中动脉线栓法建立大鼠局灶性脑梗死（MCAO）模型,将大鼠随机分为假手术组、缺血对照组、药物干预组。药物干预组于MCAO术后2h腹腔注射EDS20mg／（kg·d）,每24h给药1次,连续给药2d后测定动脉血血清丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性,同时取脑组织进行2,3,5-三氯苯基四氮唑（TTC）染色测定脑梗死体积。结果MCAO术后48h,药物干预组的血清MDA含量明显降低,SOD活性增高,梗死体积较缺血对照组明显减小,两组之间的差异均有显著性（P小于0．05或0．01）。结论EDS能拮抗脑缺血引起的SOD活性下降及MDA含量增高,具有抑制脑组织脂质过氧化损伤的作用。     

Effect of Temperature and Moisture on the Physical Stability of Binary and Ternary Amorphous Solid Dispersions of Celecoxib

The effectiveness of different polymers, alone or in combination, in inhibiting the crystallization of celecoxib (CEX) from amorphous solid dispersions (ASDs) exposed to different temperatures and relative humidities was evaluated. It was found that polyvinylpyrrolidone (PVP) and PVP-vinyl acetate formed stronger or more extensive hydrogen bonding with CEX than cellulose-based polymers. This, combined with their better effectiveness in raising the glass transition temperature (T_g) of the dispersions, provided better physical stabilization of amorphous CEX against crystallization in the absence of moisture when compared with dispersions formed with cellulose derivatives. In ternary dispersions containing 2 polymers, the physical stability was minimally impaired by the presence of a cellulose-based polymer when the major polymer present was PVP. On exposure to moisture, stability of the CEX ASDs was strongly affected by both the dispersion hygroscopicity and the strength of the intermolecular interactions. Binary and ternary ASDs containing PVP appeared to undergo partial amorphous–amorphous phase separation when exposed 94% relative humidity, followed by crystallization, whereas other binary ASDs crystallized directly without amorphous–amorphous phase separation.     

甘草次酸长循环固体脂质纳米粒的制备与体外性能研究

目的:制备甘草次酸长循环固体脂质纳米粒(GA-LSLN),并对其体外性能进行考察。方法:采用乳化溶剂挥发-高压匀质法制备GA-LSLN,测定其粒径、Zeta电位、包封率和载药量,并对其体外释药进行研究;同时以地塞米松(DEXA)、游离甘草次酸(GA)和GA-LSLN作用于肝癌细胞SK-Hep-1和急性髓细胞白血病细胞MV4-11,采用MTT法考察细胞毒性。结果:GA-LSLN的平均粒径为130.1nm,Zeta电位为-36.2mV,包封率为94.6%,载药量为11.3%,其体外释放规律符合一级速率过程。DEXA、GA和GA-LSLN对SK-Hep-1细胞的半数抑制浓度(IC50)分别为(199±10)、(32±7)、(141±5)μmol.L-1,对MV4-11的IC50分别为(25±3)、(20±5)、(63±4)μmol.L-1。结论:制备的GA-LSLN粒径、包封率和载药量均较理想,药物能达到缓释的作用,GA和GA-LSLN对肝癌细胞和白血病细胞均有较强的细胞毒性。     

过程性因素对固体分散体稳定性的影响

固体分散体是改善难溶性药物溶解度、溶出行为和生物利用度的有效途径,但固体分散体稳定性差已成为制约以固体分散技术为基础的给药系统市场化的瓶颈问题。本文探讨制备方法、制剂工艺、储存条件等过程性因素对固体分散体的重结晶、药物成分含量、溶出、外观等稳定性的影响,为固体分散体研究与开发提供指导。     

Detrimental Effect of the Film Coat Chemistry and Thickness on the Physical Stability of Amorphous Solid Dispersions in Tablet Formulations

Amorphous solid dispersions (ASDs) have been widely utilized to enhance the bioavailability of pharmaceutical drugs with poor aqueous solubility. The role of various excipients on the amorphous drug to crystalline form conversion in ASDs has been widely documented. However, there has been no published study to investigate the role of film coating material on the physical stability of an ASD based tablet formulation, to the best of our knowledge. Here we show that the film coating can potentially have a detrimental impact on the physical stability of spray dried intermediates (SDI) in tablet formulations. The impact of the film coating on the physical stability of SDI was found to be related to the film coat material composition, and an increase in the film coating thickness led to a reduction in the physical stability of SDI in tablets. Oral compressed tablets in which the film coat material was “mixed-in” with the formulation blend showed a similar or worse physical stability than film coated tablets, further underscoring the film coat material impact on physical stability, independent of the film coating process. This study demonstrates a need for careful consideration of the film coat material selection for ASD based pharmaceutical product development.     

Influence of Glass Forming Ability on the Physical Stability of Supersaturated Amorphous Solid Dispersions

In this study, the influence of the glass-forming ability (GFA) of a drug on its physical stability in a supersaturated solid dispersion was investigated. Nine drugs were classified according to their GFA using their respective critical cooling rate. Their respective solubility in poly(vinylpyrrolidone-co-vinyl acetate) 6:4 (PVPVA64) was predicted using the melting point depression method based on the Flory-Huggins lattice theory. Supersaturated amorphous solid dispersions at a level of 25% w/w drug above saturation solubility in the polymer were prepared by film-casting, and their respective physical stability at temperatures of 10°C or 20°C above or below their respective T_g (dry conditions) was monitored by the use of polarized light microscopy. This study showed that drugs with good GFA (class 3) on average have higher physical stability in supersaturated amorphous solid dispersion compared to drug with modest GFA (class 2), which in turn have higher physical stability in supersaturated amorphous solid dispersion than drugs with poor GFA (class 1). These results indicate that the GFA of a drug and its physical stability in a supersaturated amorphous solid dispersion stored at a temperature above or below its T_g are correlated.     

薄膜分散-超声法工艺参数对烟酸姜黄素酯纳米粒粒径及包封率的影响

摘 要 目的：探索薄膜分散 超声法制备烟酸姜黄素酯固体脂质纳米粒的工艺参数对其粒径及包封率的影响,以期获得制备粒径小、包封率高的工艺参数。方法: 采用HPLC法测定烟酸姜黄素酯的含量,以烟酸姜黄素酯固体脂质纳米粒粒径及包封率为评价指标,通过正交设计试验法、95%可信区间重叠法统计分析,优选薄膜分散 超声法制备烟酸姜黄素酯固体脂质纳米粒粒径小、包封率高的工艺参数。结果:烟酸姜黄素酯固体脂质纳米粒的最佳工艺参数为：水浴温度40℃,茄型瓶旋转速度80 r·min^-1。制得的固体脂质纳米粒平均粒径为107.8 nm,聚合物分散性指数（PDI）为0.583,包封率为68.91%。结论:茄型瓶旋转速度对薄膜分散 超声法制备烟酸姜黄素酯固体脂质纳米粒的粒径影响较大,而水浴温度对其包封率影响较大,两者兼顾考虑,在优选的工艺条件下,可获得平均粒径较小、包封率较高的烟酸姜黄素酯固体脂质纳米粒。     

姜黄素固体脂质纳米粒单用或与顺铂联用对人卵巢癌SKOV3细胞增殖的抑制作用研究

目的:研究姜黄素固体脂质纳米粒(Cur-SLN)单用或与顺铂(DDP)联用对人卵巢癌SKOV3细胞增殖的抑制作用。方法:单用试验,分组为空白对照组、Cur组、Cur-SLN组(均以Cur计,终浓度为10、20、40、60、80μmo·lL-1);联用试验,分组为空白对照组、DDP组、DDP+Cur组及DDP+Cur-SLN组,各组DDP终浓度为1、2、3、4、5μmo·lL-1,Cur终浓度均为10μmo·lL-1,检测上述各组分别对SKOV3细胞作用24、48、72h后细胞的生长抑制率。另设立空白对照组、DDP组、Cur组、Cur-SLN组、DDP+Cur组及DDP+Cur-SLN组(DDP终浓度均为2.5μmo·lL-1,Cur终浓度均为10μmo·lL-1),检测各组对SKOV3细胞作用24h后细胞凋亡率及细胞周期调控因子Cyclin E、CDK2的表达。结果:相同浓度下,与Cur组比较,Cur-SLN组作用不同时间后细胞生长抑制率均明显升高(P<0.05);与DDP组比较,DDP+Cur组和DDP+Cur-SLN组细胞生长抑制率均明显升高(P<0.05),且DDP+Cur-SLN组明显高于DDP+Cur组(P<0.05);与空白对照组比较,5个药物组细胞阻滞主要发生在G2期,细胞凋亡率和Cyclin E、CDK2表达均明显升高(P<0.05或P<0.01),且DDP+Cur-SLN组明显高于其他组(P<0.05)。结论:Cur-SLN对人卵巢癌SKOV3细胞有明显的生长抑制及促凋亡作用,且与DDP联用有协同效果。