Preparation of berberine hydrochloride long-circulating liposomes by ionophore A23187-mediated ZnSO_(4)gradient method

The aim of the study was to prepare berberine hydrochloride long-circulating liposomes and optimize the formulation and process parameters,and investigate the influence of different factors on the encapsulation efficiency.Berberine hydrochloride liposomes were prepared in response to a transmembrane ion gradient that was established by ionophore A23187.Free and liposomal drug were separated by cation exchange resin,and then the amount of intraliposomal berberine hydrochloride was determined by UV spectrophotometry.The optimized encapsulation efficiency of berberine hydrochloride liposomes was 94.3%
2.1%when the drug-to-lipid ratio was 1:20,and the mean diameter was 146.9 nm
3.2 nm.As a result,the ionophore A23187-mediated ZnSO_(4)gradient method was suitable for the preparation of berberine hydrochloride liposomes that we could get the desired encapsulation efficiency and drug loading.

Analytical methods for investigating in vivo fate of nanoliposomes:A review

Nanoliposomes are considered to be the most successful nanoparticle drug delivery system, but their fate in vivo has not been fully understood due to lack of reliable bioanalytical methods, which seriously limits the development of liposomal drugs. Hence, an overview of currently used bioanalytical methods is imperative to lay the groundwork for the need of developing a bioanalytical method for liposome measurements in vivo. Currently, major analytical methods for nanoliposomes measurement in vivo include fluorescence labeling, radiolabeling, magnetic resonance imaging（MRI）, mass spectrometry and computed tomography. In this review, these bioanalytical methods are summarized, and the advantages and disadvantages of each are discussed. We provide insights into the applicability and limitations of these analytical methods in the application of nanoliposomes measurement in vivo, and highlight the recent development of instrumental analysis techniques. The review is devoted to providing a comprehensive overview of the investigation of nanoliposomes design and associated fate in vivo, promoting the development of bioanalytical techniques for nanoliposomes measurement, and understanding the pharmacokinetic behavior, effectiveness and potential toxicity of nanoliposomes in vivo.

Study on State of Terbium Ion in Liposome by One order Derivative Fluorescence Quenching Method

The state of Tb3+ is investigated in liposome. When the concentration of PC is below CMC (critical micell concentration), most of Tb3+ is associated with PC, the binding constant is about 3.35×103 L/mol. When the concentration of PC is beyond CMC, most of Tb3+ is dimerized, the dimerization constant is about 3.92×104L/mol. In PC?CH?H2O system, the binding constant of Tb3+?CH complex 2.93×104L/mol is obtained.

Development and assessment of tyrosinase inhibitory activity of liposomes of Asparagus racemosus extracts

The purpose of this study was to develop liposomal formulations of Asparagus racemosus root extract(AR1-6)as well as evaluate the physicochemical properties and in vitro tyrosinase inhibitory activity.Liposomes composed of AR1-6 to lipid weight ratio of 1:10 and lecithin(LEC)or Phospholipon
90G(PC90G)as structural phospholipid at 7:3 molar ratio to CHOL were prepared by various methods,i.e.chloroform-film(CF),reverse-phase evaporation(REV),polyol dilution(PD),and freeze-drying of monophase solution(MFD)methods.The results revealed that vesicles prepared by CF and MFD were multilamellar whereas those prepared by REV and PD were oligolamellar in nature with particle sizes ranging from 0.26 to 13.83 mm.The zeta potentials were in the range of
1.5 to
39.3 mV.AR1-6 liposomes with LEC possessed significantly higher entrapment than those with PC90G.The highest entrapment efficiency and in vitro tyrosinase inhibitory activity of 69.08%and 25%,respectively,were obtained from liposomes having LEC and prepared by PD method.The tyrosinase inhibitory activity were in the rank order of LEC>PC90G,and PD>CF>REV>MFD.It could be concluded that the mechanism of vesicle forming in each method of preparation was the key factor influencing physicochemical properties,particularly vesicle type,size,surface charge,and entrapment,which were well correlated with the biological activity.

Evaluation of the Permeation and Penetration of Two Formulations of Terbinafine Chlorhydrate Incorporated in Liposomes (Cream 1%) vs. a Conventional Formulation (Cream 1%), in an <i>in Vitro-ex Vivo</i>Model

In this trial, a topical formulation of a 1% liposome TH cream was compared to a conventional TH formulation. Permeation was evaluated through a synthetic membrane. The study provided information on the rate of diffusion and percentage of drug release and also compared the penetration dynamics in the layers of the stratum corneum of both formulations. Liposome TH cream was able to deliver the active ingredient to a larger number of SC layers, with a higher amount of drug, which is very promising for the treatment of superficial mycoses.

尿石素A脂质体的制备:稳定性及体外消化研究

尿石素A具有许多优良的生理活性,但其极低的水溶性和生物利用率限制了尿石素A的应用。为克服上述限制,该文采用pH驱动法结合高压均质技术制备尿石素A脂质体(urolithin A liposomes,UA-LPs),并考察其结构特性、稳定性及体外消化特性。结果表明,大豆卵磷脂为20 mg/mL所制得的UA-LPs的平均粒径为(97.46±0.83)nm,多分散系数为(0.27±0.01),Zeta电位为(-40.3±1.06)mV,包埋率为(98.11±0.26)%,负载率为(2.39±0.01)%。UA-LPs在原子力显微镜下为分布均匀的球状结构。热稳定性实验表明,不同大豆卵磷脂浓度的UA-LPs的包埋率均随热处理时间的延长有所下降,20 mg/mL的大豆卵磷脂制备的UA-LPs具有最好的热稳定性,其在80℃处理180 min后仍可保留45%的尿石素A,且粒径、多分散系数变化趋势较小。pH稳定性表明UA-LPs在酸性条件下包埋率较低,随着pH的升高,粒径、多分散系数变化不显著(P>0.05),20 mg/mL的大豆卵磷脂制备的UA-LPs的Zeta电位绝对值上升5.5,稳定性升高。体外模拟消化实验表明,UA-LPs能有效提高尿石素A的转化率以及生物可接受度,其中20 mg/mL大豆卵磷脂制备的UA-LPs的体外转化率相比游离的尿石素A增加了3.26倍,生物可接受度提高2.07倍。因此,利用pH驱动法可以成功制备出UA-LPs,且高大豆卵磷脂浓度的UA-LPs物理稳定性更好,以上研究结果为扩展尿石素A在食品工业及生物医药领域的应用提供依据。

蜂胶脂质体制备工艺优化及抗氧化活性分析

[目的]提高蜂胶的水溶性及其生物利用率,扩大蜂胶在食品行业的应用范围。[方法]以胆固醇、大豆卵磷脂为壁材,蜂胶为芯材,利用薄膜分散法制备蜂胶脂质体。以包封率为检验指标,通过单因素试验及响应面分析法优化得到蜂胶脂质体的最佳制备工艺,并对其抗氧化活性进行分析评价。[结果]蜂胶脂质体的最优制备工艺为大豆卵磷脂用量2.5 g/100 mL,大豆卵磷脂与胆固醇质量比10.3∶1,蜂胶与胆固醇质量比3.8∶1,蜂胶脂质体的包封率可达93.09%。该法所得蜂胶脂质体在体积分数为50μL/mL时,对DPPH自由基、ABTS+自由基、羟自由基清除率分别达88.58%,61.13%,86.02%。[结论]试验制备的蜂胶脂质体包封率高,水溶性好,且具有良好的抗氧化能力。

尼达尼布纳米脂质体的制备及其表征研究

目的探讨4种不同方法制备尼达尼布脂质体的关键理化特性,筛选出尼达尼布脂质体的最佳制备方法。方法采用薄膜分散法、逆向蒸发法、乙醇注入法和改良版乙醇注入法制备尼达尼布脂质体;利用透析法测定尼达尼布脂质体的包封率,并进行粒径大小、分散性、表面电位和形貌表征,在室温放置7 d后评估其稳定性。结果薄膜分散法、逆向蒸发法、乙醇注入法和改良版乙醇注入法均制备了类圆形尼达尼布脂质体,粒径大小分别为(285.1±12.3)、(271.4±5.9)、(226.3±14.8)、(197.2±11.2)nm;包封率分别为(15.82±1.26)%、(16.71±1.35)%、(25.12±3.21)%和(32.5±3.61)%;与其他3种方法相比,改良版乙醇注入法制备尼达尼布脂质体粒径大小显著减小,包封率显著增加(P<0.05)。室温放置7 d后,薄膜分散法和逆向蒸发法粒径明显增大(P<0.01),乙醇注入法和改良版乙醇注入法粒径大小无明显差异(P>0.05)。结论改良版乙醇注入法制备的尼达尼布脂质体关键理化特性表现优异,可作为制备尼达尼布脂质体的优选方法。

逆向蒸发法制备马齿苋多糖脂质体及其免疫增强作用初探

通过单因素实验优化马齿苋多糖脂质体的制备工艺,并对其免疫增强作用进行了初步探究。以卵磷脂浓度、吐温80用量以及超声乳化时间因素,包封率为指标,单因素法优选马齿苋多糖脂质体制备工艺,再通过对小鼠脾淋巴细胞及巨噬细胞系Raw264.7细胞的毒性及增殖活性实验,观察其免疫效果。最佳工艺条件为卵磷脂浓度5 mg·mL^(-1)、吐温80用量为15∶1以及乳化超声时间5 min,在该条件下,马齿苋多糖脂质体的包封率为37.83%±1.49%,得到脂质体,其外观透明清亮呈淡蓝色乳光。小鼠脾淋巴细胞及Raw264.7巨噬细胞的最大安全浓度为63μg·mL^(-1);马齿苋多糖脂质体较马齿苋多糖及空白脂质体对于小鼠脾淋巴及Raw264.7巨噬细胞的免疫增强作用效果更显著。

鬼臼毒素脂质体的制备及其质量评价

目的 优化鬼臼毒素脂质体(POD-Lps)处方工艺并进行质量评价。方法 采用乙醇注入法制备POD-Lps,建立HPLC法测定脂质体中鬼臼毒素的含量及包封率。以包封率为指标,通过Box-Behnken响应面分析法对处方和工艺进行优化。观察其微观形态,测定其粒径、Zeta电位,并考察体外释放过程。结果 POD-Lps最优处方为:胆固醇和磷脂质量比为1∶14.49,药物和磷脂质量比为1∶32.36,磷酸盐缓冲液pH值5.82,水浴温度55℃。所得的POD-Lps包封率为(87.43±1.8)%,平均粒径为(139.12±9.81)nm,多分散系数(PDI)为(0.21±0.04),Zeta电位为(-26.37±0.36)mV。体外释放研究表明,POD-Lps具有明显的缓释效果。POD-Lps的稳定性较好,4℃条件下放置1个月后,各项指标均没有明显变化。结论乙醇注入法简单、稳定,可用于POD-Lps的制备。

基于Box-Behnken响应面法优化白芍总苷脂质体凝胶的制备工艺

目的:优化白芍总苷脂质体凝胶的制备工艺。方法:以卡波姆用量、甘油用量、三乙醇胺用量为考察因素,均匀度、透明度、流动性为质量评价标准,采用Box-Behnken响应面法优化白芍总苷脂质体凝胶的制备工艺。结果:白芍总苷脂质体凝胶最佳制备工艺的卡波姆用量为2 g,甘油用量为90 g,三乙醇胺用量为30 g。结论:优化后的白芍总苷脂质体凝胶制备工艺制备出的白芍总苷脂质体凝胶外观均匀、透明度高、流动性好。优化后的白芍总苷脂质体凝胶制备工艺稳定可行,可以代替现有的传统制备工艺,应用于临床治疗。

Optimization of preparation process of cationic liposome nanoparticles containing Survivin-siRNA and osthol

Objective:To prepare cationic liposome nanoparticles loaded with survivin-siRNA and Cnidium monnieri based on the ability of liposomes to contain both water-soluble and lipid soluble components.Methods:The preparation technology of Osthol cationic liposomes was optimized by orthogonal test with membrane material ratio,drug lipid ratio,ultrasonic time and steaming temperature as factors.The volume ratio of HA-siRNA to protamine and the ratio of HA-siRNA protamine complex to liposome were investigated by control variable method with potential and particle size as indexes.The particle size and zeta potential were measured by potentiometric particle size analyzer,and the shape was observed by transmission electron microscope;The absorbance of different concentrations of FAM-Survivin-siRNA standard solution was measured by microplate analyzer,and the entrapment efficiency of cationic liposomes loaded with FAM-Survivin-siRNA and osthole was calculated.Results:The optimum preparation conditions of osthole loaded cationic liposomes were as follows:the ratio of membrane to material was 3:1,the ratio of drug to lipid was 1:5,the steaming temperature was 30℃,the ultrasonic time was 70 min,and the encapsulation efficiency was 78.34%.The optimum preparation conditions of osthole loaded cationic liposomes loaded FAM-Survivin-siRNA were as follows:the volume ratio of Survivin-siRNA to protamine was 1:1,Protamine complex 25μg.Add 50μL cationic liposomes.The particle size is 132.3±0.2nm,zeta potential is 43.15±0.05mv,and its shape is irregular round;According to the standard curve,the entrapment efficiency of cationic liposome nanoparticles co loaded with Survivin-siRNA and osthole was 81.34±0.041%.Conclusion:The prepared cationic liposome nanoparticles loaded with Survivin-siRNA and osthole have good encapsulation efficiency,particle size and zeta potential.

番茄红素肝靶向脂质体制备工艺研究及肝靶向性评价

番茄红素是一种天然功能性类胡萝卜素,因化学稳定性及水溶性较差降低了生物利用率,将其制备成靶向脂质体可改善其水溶性并扩大其应用范围。实验采用探头式超声-逆向蒸发法制备以硬脂醇半乳糖苷为配体修饰的番茄红素肝靶向脂质体,单因素及响应面法优化后最佳工艺为大豆卵磷脂与胆固醇比7∶1、配体与固体脂质比1∶40、药脂比1∶48、旋蒸时间35 min、旋蒸温度51℃,在此条件下制备的脂质体包封率为(91.13±0.20)%,载药量为(2.39±0.37)%,粒径为(252.63±5.87)nm,在不同光照条件、贮藏温度以及有无氧气条件下稳定性均良好。动物实验显示番茄红素肝靶向脂质体组小鼠肝脏部位番茄红素含量最高,证明了经硬脂醇半乳糖苷修饰后,番茄红素脂质体肝靶向性增强。

阿可拉定长循环脂质体的制备与药效学评价

目的制备阿可拉定长循环脂质体(icaritin PEGylated liposomes,Ica-Lips),并评价其对人源肝癌细胞(hepaloblasloma G2,HepG2)的体内抗肿瘤效果。方法采用冷冻干燥-水化法制备Ica-Lips,并在透射电镜下观察Ica-Lips的微观形态,测定Ica-Lips的包封率、粒径分布、Zeta电位,以及在pH7.4磷酸盐缓冲液(PBS)以及大鼠血浆中的药物释放特性;并考察了Ica-Lips的稳定性;比较了Ica-Lips与Ica原料药在大鼠体内的药动学行为,评价Ica-Lips对小鼠接种人源肝癌细胞(HepG2)的抑瘤效果。结果制备的Ica-Lips呈类球状分布,其包封率为96.4%±0.3%,平均粒径为(108.4±3.6)nm,Zeta电位为(-12.9±0.2)mV;与Ica-Lips在pH7.4 PBS中的释药速率相比,其在大鼠血浆中的释药速率明显加快;Ica-Lips在低温条件下保存3个月,稳定性良好;药动学研究表明,Ica-Lips可显著延长药物在大鼠体内的滞留时间,增加药物的生物利用度;药效学研究表明,Ica-Lips对小鼠接种人源肝癌细胞(HepG2)的抑瘤效果显著高于Ica溶液(P<0.05)。结论将阿可拉定制备成长循环脂质体,提高了抗肿瘤效果,具有潜在的临床应用价值。

Plackett-Burman联用星点设计-效应面法优化龙胆苦苷脂质体制备工艺的研究

目的优选出龙胆苦苷脂质体的最佳原料处方与制备条件。方法采用Plackett-Burman(PBD)联用星点设计-效应面法(CCD-RSM)设计龙胆苦苷脂质体优化实验,紫外分光光度计与粒径仪测定包封率与粒径,确定制备龙胆苦苷脂质体的最优制备条件,根据拟合结果施行工艺验证。结果得到最优制备方案为载药温度34℃、药物与磷脂比例0.05、胆固醇与磷脂投料比0.52,此条件下所得龙胆苦苷脂质体粒径为(92.44±1.80)nm、包封率为(87.70±2.60)%。结论PBD与CCD-RSM联用实验设计策略优选出的龙胆苦苷脂质体粒径较小、包封率高,制备方案可靠,能达到满意的效果。

硫酸阿米卡星多囊脂质体的制备及评价

目的制备硫酸阿米卡星多囊脂质体(amikacin sulfate multivesicular liposomes,AMK-MVLs),对其进行质量评价,并考察了其体外抗菌活性。方法采用复乳法制备AMK-MVLs混悬液Ⅰ,Box-Behnken效应面法优化筛选最佳处方,采用生理盐水洗涤后调整药物浓度得AMK-MVLs混悬液。采用光学显微镜、激光粒度仪、差示扫描量热(differential scanning calorimeter,DSC)考察制剂的理化性质,采用透析法考察其体外释放规律,通过微量稀释法初步考察其体外抗菌活性。结果优化得到AMK-MVLs混悬液Ⅰ的最佳处方为:大豆磷脂与胆固醇质量比为1.91:1,三油酸甘油酯用量为1.02%,PVA用量为0.62%。AMK-MVLs呈堆叠有无数囊泡的非同心球状,AMK-MVLs混悬液包封率(87.12±1.55)%,平均粒径为11.93μm。DSC结果表明,AMK以无定型状态存在于脂质体内。体外释放结果显示AMK-MVLs混悬液在72 h时释药约80%。体外溶血实验表明,AMK-MVLs脂质体粒子浓度低于400μg/mL时无溶血风险。体外抗菌实验结果显示,相较于AMK溶液,AMK-MVLs混悬液对E.coli、P.aeruginosa、S.aureus 3种细菌具有更好的抗菌效果。结论成功制备了一种硫酸阿米卡星多囊脂质体,其粒径分布均匀、包封率高,释药规律符合Higuchi动力学模型,具有增强的抗菌活性。

唑来膦酸脂质体的制备及抗肿瘤活性研究

目的提高水溶性药物唑来膦酸脂质体(zoledronic acid liposomes,ZOL-LIPs)的包封率(encapsulation efficiency,EE)和载药量(drug loading,DL),降低给药剂量,增强ZOL-LIPs对乳腺癌细胞的抑制作用。方法采用逆向蒸发法制备ZOL-LIPs,通过Box-Behnken效应面法优化ZOL-LIPs的处方,用MTT法研究ZOL-LIPs对人乳腺癌MCF-7细胞的体外抑制作用。结果得到ZOL-LIPs的最优处方:药物与磷脂的质量比为0.067,磷脂与胆固醇的质量比为5.503,乙醚与PBS的体积比为1.941,其包封率为43.152%,载药量为2.257%,与预测值接近,其平均粒径为(197.3±1.7)nm,PDI为(0.170±0.027),且具有良好的缓释作用,稳定性强,与唑来膦酸水溶液相比,其对MCF-7细胞的抑制作用更强。结论采用Box-Behnken效应面法优化ZOLLIPs的处方所制备的ZOL-LIPs包封率高且粒径小,可使药物充分聚集于肿瘤组织而发挥EPR效应,为乳腺癌的治疗和预防其骨转移提供了新的方法。

类紫杉醇脂质体体外释放的桨膜结合分析法研究

体外释放度是评价脂质体制剂质量的重要指标,目前各国药典中均未收载脂质体体外释放度评价方法,致使脂质体质量评价缺乏统一标准和无法提供安全性保障。本研究以自制类紫杉醇脂质体为例,通过优化外部释放条件建立的桨膜结合法模拟了在生理条件下类紫杉醇药物12 h的释放情况,结果表明以0.5%SDS-HEPES作为释放介质,采用截留分子量为1000 kD的透析袋对脂质体水溶液进行释放的结果满足要求,且具有区分能力,为载药脂质体体外释放方法开发提供参考。

DSPE-mPEG2000修饰荷叶碱脂质体制备及其体内药动学研究

目的制备二硬脂酰磷脂酰乙醇胺-聚乙二醇2000(DSPE-mPEG2000)修饰荷叶碱脂质体,并考察其体内药动学。方法薄膜超声法制备脂质体。以磷脂酰胆碱与胆固醇比例、脂药比、DSPE-mPEG2000用量、水化温度、超声时间为影响因素,单因素试验优化处方,测定包封率、载药量、粒径、PDI、Zeta电位、体外释药。18只大鼠随机分为3组,分别灌胃给予荷叶碱原料药、不含DSPE-mPEG2000荷叶碱脂质体、DSPE-mPEG2000修饰荷叶碱脂质体的0.5%CMC-Na混悬液(20 mg/kg),于0、0.25、0.5、1、1.5、2、3、4、6、8、12 h采血,HPLC-MS/MS法测定荷叶碱血药浓度,计算主要药动学参数。结果最佳处方为荷叶碱用量20 mg,磷脂酰胆碱与胆固醇比例5∶1,脂药比12∶1,DSPE-mPEG2000用量30 mg,水化温度40℃,超声时间15 min,平均包封率为71.69%,载药量为4.59%,粒径为161.84 nm,PDI为0.163,Zeta电位为-7.17 mV。DSPE-mPEG2000修饰后,荷叶碱在人工胃液、人工肠液中48 h内累积释放度分别为66.17%、53.90%。与原料药比较,脂质体t_(max)、t_(1/2)延长(P<0.01),C_(max)、AUC_(0~t)、AUC_(0~∞)升高(P<0.01),相对生物利用度增加至6.14倍。结论DSPE-mPEG2000修饰脂质体可促进荷叶碱口服吸收。

脂质体体外释放行为评价方法研究进展

活性药物只有从脂质体中释放出来才可能在体内进一步发挥治疗作用,脂质体释药过程可通过体外释放行为来模拟,因此,体外释放行为是脂质体重要质量控制指标。文献报道的常用脂质体释放行为评价方法有取样分离法、透析法、流通池法、Franz扩散池法、ussing chamber法以及一些改良优化的方法,每种评价方法都有特定的优势和应用局限性。《中华人民共和国药典》目前并没有明确脂质体体外释放评价方法,这在一定程度上阻碍了脂质体的应用,因此,研究建立重复性好、操作性强、标准化程度高的体外释放方法是脂质体开发过程中亟待解决的问题。该文概括了近年来脂质体体外释放行为评价方法的研究现状及应用情况,分析了每种释放方法的特点,以期为脂质体体外释放行为评价方法的发展和完善提供参考。