去氢骆驼蓬碱脂质体冻干剂粉的制备工艺优选

目的:制备含有不同冻干保护剂的N-三甲基壳聚糖(TMC)包衣去氢骆驼蓬碱脂质体(TMC-HM-LP)的冻干粉,并筛选其最佳制备工艺。方法:用"薄膜分散-pH梯度法"制备去氢骆驼蓬碱脂质体,并采用孵育包衣法、低温高速离心法和结合高效液相色谱(HPLC)定量方法测定其包衣脂质体的包封率;以其冻干粉的外观在冻干前和复溶后脂质体的粒径、包封率作为对比指标,优选出最佳的冻干工艺以及冻干保护剂的种类及比例。结果:以葡萄糖-乳糖-甘露醇(2:1:0.5)作为冻干保护剂,通过"分步预冻"的方法和-80℃冷冻干燥技术得到的TMC-HM-LP外观良好,冻干前后粒径和包封率变化较小。结论:采用冷冻干燥技术并结合冻干保护剂的优选,可显著提高包衣脂质体的稳定性。     

阿苯达唑纳米脂质体冻干粉的制备及性质考察

目的:制备阿苯达唑纳米脂质体冻干粉并对其性质进行考察。方法:利用冷冻干燥法制备阿苯达唑纳米脂质体冻干粉,以粒径、包封率联合外观、再分散性为指标,采用单因素试验联合正交试验筛选冻干处方工艺。考察冻干前、后脂质体的形态学变化、粒径、Zeta电位、水分含量、4℃下12个月的稳定性。结果:采用外加冻干保护剂的总量为10%,其中葡萄糖-海藻糖-甘露醇配比为1.0∶1.0∶3.0,以速冻的方式,于-35℃冰箱预冻18 h,冷冻干燥48 h获得冻干粉。与冻干前比较,冻干后脂质体形态未发生明显变化,可见清晰的磷脂双分子层膜结构;冻干前、后脂质体的粒径分别为(208.63±1.04)、(223.04±2.02)nm,Zeta电位分别为(-15.6±0.04)、(-19.4±0.06)m V,包封率分别为(94.62±0.49)%、(91.10±0.46)%(n=3);与脂质体比较,脂质体冻干粉在4℃下12个月较稳定。结论:成功制得阿苯达唑纳米脂质体冻干粉,其稳定性优于阿苯达唑纳米脂质体,冻干工艺可行。     

聚乙二醇修饰青蒿素脂质纳米粒冻干工艺优化及其表征

目的筛选聚乙二醇(PEG)修饰青蒿素脂质纳米粒(PEG-ART-NLC)最优冻干保护剂处方,研究其冷冻干燥工艺及质量表征。方法制备含不同冻干保护剂的PEG-ART-NLC冻干粉,以外观、再分散性、复溶后外观、粒径、Zeta电位为指标,优化保护剂处方,并对比冻干前后脂质纳米粒质量变化。结果 4%甘露醇和4%蔗糖具良好的保护作用和再分散性,冻干后纳米粒粒径增大14.0 nm,Zeta电位绝对值降低8.8 m V,包封率降低14.5%,电镜下冻干前后纳米粒形态均为圆形或椭圆形,无明显差异。结论 4%甘露醇和4%蔗糖为最优保护剂处方,可用于制备稳定的PEG-ART-NLC冻干粉。     

冻干工艺及保护剂对羟基喜树碱脂质体质量的影响

用薄膜水化-高压均质法制备羟基喜树碱脂质体,以葡聚糖凝胶色谱法分离脂质体和游离药物,采用HPLC法测定包封率。通过差示扫描量热法测定含不同保护剂的脂质体的最低共熔点和玻璃化转变温度,并比较冻干品外观、冻干前后脂质体包封率和粒径的变化,优选出最佳的冻干工艺、冻干保护剂种类及比例。结果表明,以6%蔗糖为冻干保护剂,经4℃、1 h,-18℃、12 h和-35℃、5 h逐步预冻,然后于-54℃冷冻干燥24 h,制得的冻干品外观良好,脂质体复溶后粒径变化小,包封率达(87.0±2.7)%。     

聚(2-乙基-2-噁唑啉)修饰超氧化物歧化酶模拟物脂质体冻干制剂的制备

目的:制备聚(2-乙基-2-噁唑啉)(PEOZ)修饰超氧化物歧化酶(SOD)模拟物脂质体的冻干制剂。方法:通过考察预冻方式、预冻时间、真空干燥时间及联合冻干保护剂的种类及比例等优化冻干工艺,并测定所制制剂的水化复溶时间、粒径和包封率。结果:以10%乳糖+1%甘露醇+10%海藻糖作为联合冻干保护剂,并以外加方式加入PEOZ修饰SOD模拟物脂质体中,快速冷冻5h,真空干燥30h,可得到外观光洁、平整的目标冻干制剂;其水化复溶时间为(10±1)s,粒径为(159.3±10.2)nm,包封率为86.25%(RSD=3.26%,n=6)。结论:该优化冻干工艺质量可控,重复性好。     

紫杉醇长循环热敏前体脂质体的制备与表征

目的:研究紫杉醇长循环热敏前体脂质体的制备并对其性质进行考察.方法:采用薄膜分散法制备紫杉醇长循环热敏脂质体,再用冷冻干燥技术制备紫杉醇长循环热敏前体脂质体;采用激光粒度仪考察粒径和Zeta电位;采用高效液相色谱法研究其含量与包封率;并考察脂质体的体外释药特性.结果:紫杉醇长循环热敏前体脂质体水合后形成紫杉醇长循环热敏脂质体,粒径均值为(108.6 ±3.6)nm,Zeta电位的均值为(-12.2±1.8)mV,包封率可达96.2％;该脂质体在相变温度42℃下药物释放达到95％以上.结论:紫杉醇长循环热敏前体脂质体的制备工艺稳定,载药量大,包封率高,具有良好的热敏性;含量及其包封率测定方法简单、快速、准确.本实验可为紫杉醇静脉注射用新制剂的开发提供研究基础.     

全反式维甲酸前体脂质体的制备及体外评价

目的:制备维甲酸前体脂质体,并对其体外性质进行考察。方法:采用乙醇注入结合冷冻干燥法制备前体脂质体;微柱离心-高效液相色谱法测定脂质体的包封率;并进一步对其粒径、Zeta电位、血浆释放率及乙醇残留量进行测定。结果:所制备的前体脂质体包封率为95.2%,Zeta电位为-(28.4±17.5)mV,粒径为(170±29)nm,乙醇残留量为3.98%。结论:乙醇注入结合冷冻干燥法制备的维甲酸前体脂质体包封率高,粒径均匀,稳定性好。     

依托泊苷长循环热敏前体脂质体的制备工艺研究

目的:对依托泊苷(Etoposide,VP-16)长循环热敏前体脂质体的制备工艺进行研究,并对该制备工艺进行方法学及制剂质量考察。方法:应用薄膜分散法制成VP-16长循环热敏脂质体,进一步借助冷冻干燥技术进行依托泊苷长循环热敏前体脂质体的制备;采用zeta电势测定仪及HPLC等技术进行方法学考察,主要包括脂质体的包封率、粒径、载药量、电位、释放度、稳定性。结果:VP-16长循环热敏前体脂质体水合形成长循环热敏脂质体,粒径为(105.2±3.4)nm,Zeta电位为(-11.9±1.7)m V,包封率可达96.8%;该脂质体在相变温度42℃下药物释放达到96%以上。结论:VP-16长循环热敏前体脂质体的制备工艺稳定,脂质体载药量大,包封率高;药物含量及包封率的测定方法简单、快速而准确,因而,该研究可为VP-16开发成静脉注射用新制剂提供数据支持。     

卡铂前体脂质体的制备及安全性的初步评价

目的：制备卡铂前体脂质体,并对用药安全性进行初步评价.方法：采用薄膜挤压法制备卡铂脂质体,加入冻干支持剂冷冻干燥后得到卡铂前体脂质体.对豚鼠全身用药的过敏性、家兔全身用药的血管刺激性以及溶血性进行考察.结果：制备所得的卡铂前体脂质体水合后的包封率为72.0%,载药量为24.0%,平均粒径为125.1 nm.卡铂前体脂质体不引起豚鼠过敏反应,不引起家兔溶血和红细胞凝集反应,静脉注射对家兔血管无刺激性.结论：制备所得的卡铂前体脂质体有较高的包封率和载药量,水合后粒径均匀,形态圆整,且具有较好的用药安全性.     

两性霉素B长循环脂质体冻干剂的制备工艺研究

目的:对两性霉素B长循环脂质体的冻干工艺进行研究,制备两性霉素B长循环脂质体的冻干剂.方法:采用薄膜-超声法制备了两性霉素B长循环脂质体混悬液.以冻干品再分散后的粒径、包封率为评价指标,考察了不同种类的冻干保护剂和浓度对脂质体冻干品的影响,并对冻干工艺参数进行了优化.结果:选择海藻糖为冻干保护剂,冻干效果较好.制备的冻干剂的平均粒径为(116.8±1.6)nm,药物包封率为(76.0±1.9)%.结论:通过冻干保护剂的筛选和优化冻干工艺参数可以获得最佳的两性霉素B长循环脂质体的冻干品.     

反义寡核苷酸脂质体复合物性质对细胞摄入行为的影响

目的研究影响反义寡核苷酸脂质体复合物的性质和细胞摄取的因素。方法逆相蒸发法制备3种不同的空白脂质体,与反义寡核苷酸混合得到复合物,显微镜观察其形态,琼脂糖电泳分析载药量,流式细胞仪测定阳性细胞百分率和平均荧光强度。结果高电荷密度的脂质体和低离子强度介质可使复合物发生凝聚,载药量和细胞摄入量依赖于空白脂质体和药物的比例以及脂质体膜表面的电荷密度。结论阳离子脂质体可以提高载药量和细胞的摄入,其程度与复合物比例、脂质体膜表面电荷密度等有关。     

洛伐他汀自组装前体脂质体的制备及其理化性质的研究

目的:为研究洛伐他汀新剂型,制备洛伐他汀新型前体脂质体,并对其质量进行考察。方法:采用一种新型前体脂质体制备方法将洛伐他汀制成自组装前体脂质体,对水合后脂质体的形态、粒径、Zeta电位、包封率、自组装速度、稳定性等进行考察,验证这种新型前体脂质体制备方法用于制备洛伐他汀脂质体的可行性。结果:所形成的洛伐他汀脂质体包封率为95.4%±6.7%,平均粒径为(327.4±29.6)nm,Zeta电位值为-(22.4±1.5)mV。洛伐他汀自组装前体脂质体可在60 s内自发形成脂质体并达到分散平衡;以人工胃液为稀释介质,洛伐他汀脂质体在12 h内稳定。结论:采用新型前体脂质体制备方法可将洛伐他汀制成洛伐他汀脂质体,形成的脂质体包封率较高且具有良好的稳定性。     

槲皮素前体脂质体的质量考察

目的制备液体型槲皮素前体脂质体,并对制剂质量进行考察。方法采用一种新型前体脂质体制备方法制备液体型槲皮素前体脂质体,将脂质体膜材和药物等以一定比例溶于分散介质中,形成一种无水的澄明溶液。考察其水合后粒子形态、粒径、电位、包封率及自组装速度等理化性质,并评价其体外释药性质。结果槲皮素前体脂质体遇水即可快速自组装成纳米级含药脂质体混悬液,水合后形态多为类球形,平均粒径为228.7nm,Zeta电位为21.2 mV,包封率可达90%以上,体外释药符合Higuchi方程。结论槲皮素口服前体脂质体制备工艺简单可行,包封率高,具有一定的缓释效果。     

Synergistic absorption enhancement of salmon calcitonin and reversible mucosal injury by applying a mucolytic agent and a non-ionic surfactant

Using high sensitivity differential scanning calorimetry (HSDSC), the phase transitions of dimyristoylphosphatidylcholine (DMPC) liposomal bilayers and their interaction with the model steroid beclometasone dipropionate (BDP) were found to be dependent on the method of liposome manufacture. Ethanol-based proliposomes produced liposomes having no phospholipid pretransition, a main transition of high enthalpy and a low onset temperature, and a very low incorporation of the steroid (maximum 1 mol%). This was attributed to an alcohol-induced interdigitation of the bilayers, which was not apparently reversed by flushing the liposome dispersion with nitrogen in an attempt to remove ethanol. For liposomes manufactured by thin film or particulate-based proliposome methods, 1–2.5 mol% steroid was optimal for incorporation within bilayers, although the nature of the steroid interaction with the bilayers differed between the two methods. For liposomes manufactured by the thin film method, a higher steroid concentration resulted in a broadened main transition and a reduced melting cooperativity. This suggests that BDP formed separate domains within the bilayers which caused non-ideal mixing and phase separation at 5 mol% steroid. This observation was absent for liposomes generated from particulate-based proliposomes, indicating separate steroid domains were not formed and subsequent non-ideal mixing and phase separation did not occur. In addition, liposomes generated from particulate-based proliposomes showed reduced pretransition and main transition enthalpies. These differences were attributed to the employment of sucrose to manufacture the particulate-based proliposomes. This study has shown that the thermal behaviour of liposomes and their interaction with beclometasone dipropionate were dependent on the method of liposome manufacture. Moreover, particulate-based proliposomes may provide a reasonable alternative to the conventional thin film method in producing liposomes incorporating this steroid.     

Mixed micelle proliposomes for preparation of liposomes containing amphotericin B, in-vitro and ex-vivo studies

The aim of this work was to produce a form of injectable liposomes containing amphotericin B derived from mixed micelle proliposomes. Mixed micelles were derived from a mixture of lecithin/sodium cholate in aqueous media. The solubility of amphotericin B in proliposomes was studied as a function of lipid composition (total lipid concentration, molar ratio of lecithin/sodium cholate), and the dispersion media (pH, ionic strength, presence or absence of human serum albumin), and the temperature. The data show that micelle-->liposome transformation occurs during the dilution of proliposomes containing amphotericin B. These transformations could be followed via transmission electron microscopy (TEM). Data related to dilution of proliposomes as well, show that under no circumstance there occurs any precipitation that might be assigned to the decreased solubility of amphotericin B. These indicate that the incorporated drug also participates during the transformation of the proliposomes into liposomes. It is thus concluded that mixed micelle proliposomes are prime candidates for the production of a form of injectable amphotericin B in liposomes.     

依托泊苷隐形前体脂质体的构建及家兔体内药动学研究

构建依托泊苷隐形前体脂质体，并考察其在家兔体内的药动学。采用薄膜分散法构建窄白隐形脂质体；硫酸铵梯度法包封依托泊苷；结合真空冷冻干燥技术构建依托泊苷隐形前体脂质体。采用凝胶色谱法测定脂质体包封率；透射电镜观察脂质体的形态；电泳光散射技术测定Zeta电位与粒径分布；以市售依托泊苷注射液和普通脂质体为参比制剂，评价其在家兔体内药动学特点。脂质体平均包封率为83．92％±3．65％，粒径为（124．5±26．9）nm，Zeta电位为（-39．50±1．04）mV，家兔单剂量静脉注射1．5mg／kg依托泊苷制剂后呈二室模型特征，依托泊苷隐形前体脂质体的T1/2β为（19．26±3．16）h，AUC为（26．04±3．53）μg／h／mL；注射液的T1/2β为（0．94±0．21）h，AUC为（0．98±0．26）μg／h／mL；普通脂质体的T1/2β为（7．99±1．36）h,AUC为（11．65±1．70）μg/mL。构建的隐形前体脂质体包封率高，且延长了依托泊苷在血液中的循环时间。     

Preparation of coenzyme Q10 liposomes using supercritical anti-solvent technique

Coenzyme Q(10) (CoQ(10)) proliposomes were prepared using the supercritical anti-solvent (SAS) technique to encapsulate CoQ(10). The mixture of cholesterol and soya bean phosphatidylcholine (PC) was chosen as wall materials. The effects of operation conditions (temperature, pressure and components) on the recovery of CoQ(10) and the CoQ(10) loading in CoQ(10) proliposomes were studied. At the optimum conditions of pressure of 8.0?MPa, temperature of 35°C, the weight ratio of 1/10 between CoQ(10) and PC, and the weight ratio of 1/3 between cholesterol and PC, the CoQ(10) loading reached 8.92%. CoQ(10) liposomes were obtained by hydrating CoQ(10) proliposomes and the entrapment efficiency of CoQ(10) reached 82.28%. The morphologies of CoQ(10) proliposomes were characterized by scanning electron microscope, and their solid states were characterized by X-ray diffractometer. The structures of CoQ(10) liposomes were characterized by transmission electron microscope. The particle size distribution of CoQ(10) liposomes was determined by dynamic light scattering instrument. The results indicate that CoQ(10) liposomes with particle sizes about 50?nm can be easily obtained from hydrating CoQ(10) proliposomes prepared by SAS technique.     

反义寡核苷酸阳离子脂质体的制备和体外细胞摄取研究反义寡核苷酸阳离子脂质体的制备和体外细胞摄取研究

目的制备高效促进细胞摄取反义寡核苷酸(ASON)和保护ASON的脂质体。方法以3β［n-(n′,n′-二甲氨基乙基)氨甲酰基-胆固醇(DC-Chol)为类脂成分制备阳离子脂质体(以下简称DC-Chol脂质体),与ASON混合得到载药脂质体,测定载药率。用琼脂糖凝胶电泳分析载药脂质体的结构特点;流式细胞仪检测不同条件下细胞摄取荧光标记ASON的情况;变性聚丙烯酰胺电泳考察DC-Chol脂质体对ASON的保护作用。结果载药率与DC-Chol脂质体和药物的+/-电荷比有关,当+/-电荷比大于2时,载药率达90%以上;琼脂糖凝胶电泳显示ASON同时存在于DC-Chol脂质体的周围和包裹于其内部的两种形式;流式细胞仪测定结果表明,DC-Chol脂质体可明显增加细胞对ASON的摄取,阳性细胞染色率和胞内平均荧光强度均较对照组有明显增加,增加程度主要取决于+/-电荷比例,血清可降低细胞的摄取;变性聚丙烯酰胺电泳证实DC-Chol脂质体具有保护ASON的作用。结论DC-Chol脂质体具有显著增加细胞摄取ASON和保护ASON的作用,有望成为反义类药物的高效传递系统。     

Chitosan‐coated antifungal formulations for nebulisation

Objectives The aim of this study was to produce and characterise amphotericin B (AmB) containing chitosan‐coated liposomes, and to determine their delivery from an air‐jet nebuliser. Methods Soya phosphatidylcholine : AmB (100 : 1) multilamellar vesicles were generated by dispersing ethanol‐based proliposomes with 0.9% sodium chloride or different concentrations of chitosan chloride. These liposomes were compared with vesicles produced by the film hydration method and micelles. AmB loading, particle size, zeta potential and antifungal activity were determined for formulations, which were delivered into a two‐stage impinger using a jet nebuliser. Key findings AmB incorporation was highest for liposomes produced from proliposomes and was greatest (approximately 80% loading) in chitosan‐coated formulations. Following nebulisation, approximately 60% of the AmB was deposited in the lower stage of the two‐stage impinger for liposomal formulations, for which the mean liposome size was reduced. Although AmB loading in deoxycholate micellar formulations was high (99%), a smaller dose of AmB was delivered to the lower stage of the two‐stage impinger compared to chitosan‐coated liposomes generated from proliposomes. Chitosan‐coated and uncoated liposomes loaded with AmB had antifungal activities against Candida albicans and C. tropicalis similar to AmB deoxycholate micelles, with a minimum inhibitory concentration of 0.5 µg/ml. Conclusions This study has demonstrated that chitosan‐coated liposomes, prepared by an ethanol‐based proliposome method, are a promising carrier system for the delivery of AmB using an air‐jet nebuliser, having a high drug‐loading that is likely to be effectively delivered to the peripheral airways for the treatment of pulmonary fungal infections.