紫外分光光度法测定维甲酸凝胶的含量

目的：建立维甲酸凝胶中维甲酸的含量测定方法。方法：以无水乙醇为溶媒,用紫外分光光度法直接测定维甲酸凝胶中维甲酸的含量。结果：该方法测得维甲酸平均回收率为99.76%,RSD为1.16%。结论：该方法基质无干预。方法简捷。结果准确。     

维甲酸软膏的质量控制

目的：建立维甲酸软膏的质量控制方法。方法：高效液相色谱法对维甲酸软膏进行含量测定。结果：维甲酸在2～50ug·ml^-1范围内线性关系良好（r=0．9997）,平均回收率为99．7％,RSD为1．2％。结论：该方法简便、快速、准确,可作为维甲酸软膏的质量控制。     

高效薄层扫描法同时测定复方维甲酸霜中维甲酸和维生素E…

建立了高效薄层扫描法同时测定复方维甲酸霜中维甲酸和维生素Ｅ含量的方法。以正已烷：乙酰：甲酸（９：１：０．１）为展开剂。采用双波长反向锯齿法，测维甲酸含量时λｓ＝３５０ｎｍ，λＲ＝２５９ｎｍ，测定维生素Ｅ含量时λｓ＝２８０ｎｍ，λＲ＝３２０ｎｍ。加样回收率维甲酸为９９．２％（ＲＳＤ２．０％），维生素Ｅ为９７．０％（ＲＳＤ１．２％）。本文就不同时间及不同贮存条件下霜剂的含量进行了测定，结果室温时随放置     

导数分光光度法测定布洛芬凝胶剂的含量

目的：建立测定布洛芬凝胶剂含量的方法。方法：用一阶导数分光光度法测定布洛芬凝胶剂的含量,可以消除凝胶基质中其它凝胶剂的干扰,结果：准确,重现性好。平均回收率１００７％,ＲＳＤ＝０６２％。结论：采用一阶导数分光光度法测定布洛芬凝胶剂含量,可清除基质对测量的影响,方法简便,结果准确。     

紫外分光光度法测定复方长压啶搽剂中两组份的含量

建立复方长压啶搽剂中米诺地尔和维甲酸的含量测定方法。方法：要用紫外分光光度法同时测定复方长压啶搽剂中米诺地尔和维甲酸的含量,以一阶导数２７８．５ｎｍ处的振幅值测定米诺地尔,以零阶导数３３７ｎｍｔｈ ｒ ｋｅ ｉｑ ｙａ ｉｍｊ ｐｇ ｘｗｙｇｌｈｎｈｓｃｔ     

肤康祛斑凝胶的制备与质量控制

目的制备肤康祛斑凝胶,并建立其质量控制方法。方法以卡波姆-940为凝胶的主要基质,建立性状、鉴别、检查、含量测定等质量控制方法。采用高效液相色谱法测定熊果苷和维甲酸含量,均采用Lichrospher-C18色谱柱(4.6 mm×250 mm,5μm)。熊果苷测定条件:流动相水-甲醇(90∶10),流速1.0 mL.min-1,检测波长283 nm,进样量10μL,柱温25℃;维甲酸测定条件:流动相甲醇-水-冰醋酸(90∶10∶0.1),用三乙胺调节pH至6.5,流速1.0 mL.min-1,检测波长343 nm,进样量为10μL,柱温25℃。结果熊果苷在0.055 3～0.276 5 mg.mL-1的范围内呈良好的线性关系,r=0.999 9,平均回收率为99.89%,RSD为1.03%(n=9)。维甲酸在0.009 9～0.089 0 mg.mL-1的范围内呈良好线性关系,r=0.999 9,平均回收率为99.53%,RSD为1.08%(n=9)。结论肤康祛斑凝胶的制备工艺简单,质量可控。     

高效薄层扫描法同时测定复方维甲酸霜中维甲酸和维生素E的含量

建立了高效薄层扫描法同时测定复方维甲酸霜中维甲酸和维生素Ｅ含量的方法。以正己烷：乙醚：甲酸（９：１：０．１）为展开剂。采用双波长反射锯齿法，测维甲酸含量时λ＿ｓ＝３５０ｎｍ，λ＿Ｒ＝２９５ｎｍ，测维生素Ｅ含量时λ＿ｓ＝２８０ｎｍ，λ＿Ｒ＝３２０ｎｍ。加样回收率维甲酸为９９．２％（ＲＳＤ２．０％），维生素Ｅ为９７．０％（ＲＳＤ１．２％）。本文就不同时间及不同贮存条件下霜剂的含量进行了测定，结果室温时随放置时间的延长，主药含量均有明显的下降。     

硝酸咪康唑凝胶剂的研制

目的：制备硝酸咪康唑凝胶剂，并建立质量控制方法。方法：用卡波姆-940为基质制备凝胶剂，用紫外分光光度法测定硝酸咪康唑含量，并考察其稳定性。结果：含量测定平均回收率97.79%、RSD为0.43%(n=3，凝胶稳定性良好。结论：该凝胶剂制备工艺可行，性质稳定，质控方法简便。     

氟离子选择电极法测定脱敏凝胶中主药的含量

目的：建立脱敏凝胶中主药含量测定的方法。方法：采用氟离子选择电极法进行测定。结果：含量测定平均回收率为99.9%。结论：该方法简便、灵敏、专属性强，适用于该产品的质量控制。     

氯马斯汀凝胶滴鼻剂的制备和稳定性

目的：设计一种治疗过敏性鼻炎、过敏性皮肤病的氯马斯汀凝胶滴鼻剂的处方和制备工艺,建立制剂的质量标准,并研讨其稳定性。方法：以PVA作为凝胶基质;采用分光光度法测定含量;加速试验法考察制剂的稳定性。结果：制剂均匀、分散性好。建立的分析方法不受辅料的干扰,准确测定含量。结论：氯马斯汀凝胶滴鼻剂的制备工艺简单,易于生产。     

高效液相色谱法同时测定维A酸霜中两组分的含量

目的 :建立高效液相色谱法同时测定维A酸霜中维A酸和盐酸苯海拉明含量的方法。方法 :色谱柱为LUNAC18 柱(250mm×4 6mm ,5μm) ,流动相为甲醇 -磷酸盐缓冲液 (85∶15) ,流速为1ml/min ,检测波长为254nm ,采用外标法。结果 :维A酸、盐酸苯海拉明的线性范围分别为1 0～12 5μg/ml和10 0～133 5μg/ml ,回收率分别为98 7 % (RSD=1 1 % )和99 4 %(RSD=0 5 % )。结论 :本法可同时准确测定维A酸霜剂中维A酸和盐酸苯海拉明的含量。     

HPLC双波长法同时测定复方维A酸软膏中2主药的含量

目的:建立同时测定复方维A酸软膏中维A酸和马来酸氯苯那敏含量的方法。方法:采用高效液相色谱法。色谱柱为Luna C18柱,流动相为甲醇-磷酸盐缓冲液(0.02mo·lL-1磷酸二氢钾,用1mo·lL-1氢氧化钠调节pH至7.0,V/V)=80:20,流速为1.0mL·min-1,进样量为20μL,柱温为30℃,维A酸的检测波长为350nm,马来酸氯苯那敏的检测波长为262nm。采用外标法计算含量。结果:维A酸检测浓度在20～100μg·mL-1范围内与峰面积积分值呈良好的线性关系(r=0.9999),低、中、高平均加样回收率分别为98.48%、97.15%、98.88%(RSD=0.92%);马来酸氯苯那敏检测浓度在30～150μg·mL-1范围内与峰面积积分值呈良好的线性关系(r=0.9999),低、中、高平均加样回收率分别为100.47%、99.01%、99.75%(RSD=0.83%)。结论:该方法简便、准确、重复性好,可用于复方维A酸软膏的质量控制。     

Niosomes as carriers for tretinoin. I. Preparation and properties

Tretinoin-loaded niosomes were prepared from polyoxyethylene (4) lauryl ether, sorbitan esters and a commercial mixture of octyl/decyl polyglucosides, in the presence of cholesterol and dicetyl phosphate. Liposomes made of hydrogenated and non-hydrogenated phosphatidylcholine were also prepared as a comparison reference. A study was made of the influence of vesicle composition and preparation method on the vesicle structure (MLV, LUV, SUV), size distribution, entrapment efficiency and in vitro release of incorporated tretinoin. Results showed that in the presence of cholesterol all the amphiphiles used were able to form stable vesicle dispersions with or without tretinoin. Vesicle sizes were dependent on the preparation method, bilayer composition and drug load. Multilamellar (MLV) vesicles were larger than extruded (LUV) and sonicated (SUV) vesicles while drug-loaded vesicles were generally smaller than empty ones. Entrapment efficiencies of tretinoin were always very high especially for multilamellar (91-99%) and extruded (88-98%) vesicles. The in vitro release of tretinoin from the prepared vesicular formulations was studied using the vertical Franz diffusion cells. The rate of drug release through a Silastic membrane from a liposomal and niosomal tretinoin dispersion was generally faster than from a tretinoin solution. Release data showed that tretinoin delivery is mainly affected by the vesicular structure and that tretinoin delivery increased from MLVs to LUVs to SUVs.     

固体脂质纳米粒作为维A酸经皮给药载体的研究

目的:采用固体脂质纳米粒作为维A酸载体以提高其稳定性,增加经皮给药时的局部药物浓度。方法:采用纳米乳法制备维A酸固体脂质纳米粒,通过相图研究确定处方组成并通过单因素试验进行优化,采用葡聚糖G50微型凝胶柱测定包封率。对维A酸固体脂质纳米粒稳定性、释放度、经皮渗透性和皮肤贮留量进行评价。结果:制得的固体脂质纳米粒为球形或类球形粒子,平均粒径为83.2 nm,包封率>95%。4℃,25℃和40℃避光贮存3个月,含量和包封率均无明显变化。其体外释放速率和经皮渗透速率较市售乳膏慢,皮肤贮留量大于市售乳膏。结论:固体脂质纳米粒作为维A酸载体有助于提高其稳定性,增加局部药物浓度。     

Investigation of the chemical stability of an erythromycin-tretinoin lotion by the use of an optimization system

A combination of 2% erythromycin and 0.05% tretinoin in an alcohol-isopropanol lotion was prepared. Two parameters were investigated for their influence on the stability of erythromycin and/or tretinoin, namely pH and the concentration of butylhydroxytoluene (BHT) as antioxidant. To investigate these two parameters, an optimization technique was used with two factors (pH and concentration of BHT) at two levels. Accelerated stability analysis was performed at 45 degrees C in the dark to exclude isomerization of tretinoin. To analyse erythromycin and tretinoin in the combination preparation, a TLC method, previously developed in the laboratory, was used. The degradation of erythromycin seemed to be much faster than the tretinoin degradation. Optimal stability is shown in the pH range of 8.2-8.6 for erythromycin and 7.2-8.2 for tretinoin while the concentration of BHT had no significant influence.     

醋酸钙梯度法制备维A酸脂质体

目的:评价醋酸钙梯度法制备维A酸脂质体的可行性,并与薄膜法、逆相蒸发法进行质量比较。方法:采用薄膜法、逆相蒸发法和醋酸钙梯度法分别制备维A酸脂质体,用G-50葡聚糖凝胶柱分离,以紫外分光光度法和纳米激光粒度仪分别测定维A酸脂质体的包封率和粒径,以电子显微镜观察维A酸脂质体的形态。结果:以醋酸钙梯度法制备的维A酸脂质体包封率最高,达90.48%;其外观圆整均匀,平均粒径为35.8nm,4℃放置3mo质量稳定。结论:采用醋酸钙梯度法制备维A酸脂质体包封率较高,方法可行。     

A rapid HPLC method for simultaneous determination of tretinoin and isotretinoin in dermatological formulations

A rapid method using an isocratic high-pressure liquid chromatography and UV detection for determination of both all-trans retinoic acid (tretinoin) and 13-cis retinoic acid (isotretinoin) in dermatological preparations is presented. Tretinoin and isotretinoin samples were extracted with acetonitrile by a procedure that can be completed in less than 10 min. Subsequent separation and quantification of amounts as low as 10 pmol was accomplished in less than 15 min using reversed-phase HPLC with isocratic elution with 0.01% trifluoroacetic acid (TFA)/acetonitrile (15:85, v/v). Validation experiments confirmed the precision and accuracy of the method. When applied to commercial tretinoin samples, recoveries of 104.9% for cream formulations and 107.7% for gel formulations were obtained. Application of the method for analysis of a tretinoin cream exposed to solar simulated light (SSL) demonstrated detection of the major photoisomerization product isotretinoin as well as 9-cis retinoic acid, demonstrating the utility of the method for studies of tretinoin photostability. The method should also facilitate studies of the formulation compatibility and photocompatibility of tretinoin with agents that may improve its clinical tolerability.     

复方莪术油乳膏的制备及质量控制

目的:制备复方莪术油乳膏并建立其质量控制方法。方法:选用适宜基质,将莪术油和维A酸分别用β-环糊精包裹制成水包油型乳膏,采用紫外分光光度法测定维A酸的含量,并考察其稳定性。结果:维A酸检测浓度线性范围为1~8μg/ml(r=0·9997),平均回收率为100·7%。结论:本制剂制备工艺合理,质量控制方法简便、可行,制剂质量稳定性良好。     

Nanosuspension improves tretinoin photostability and delivery to the skin

The aims of this work were to improve cutaneous targeting and photostability of tretinoin by using nanosuspension formulation. Tretinoin is a drug widely used in the topical treatment of various dermatological diseases. The tretinoin nanosuspension was prepared by precipitation method and then characterized by photo correlation spectroscopy for mean size and size distribution, and by transmission electron microscopy for morphological studies. An oil in water tretinoin nanoemulsion was also prepared and used as a control. Dermal and transdermal delivery of both tretinoin nanosuspension and nanoemulsion were tested in vitro by using Franz diffusion cells and newborn pig skin. Photodegradation studies were carried out by UV irradiation (1 h, λ = 366 nm) of the tretinoin nanosuspension in comparison with the nanoemulsion and a methanolic solution of the drug. During 8 h percutaneous experiments, the nanosuspesion was able to localize the drug into the pig skin with a very low transdermal drug delivery, whereas the nanoemulsion greatly improved drug permeation. UV irradiation of the nanosuspension showed a great improvement of tretinoin stability in comparison with both controls. Overall results show that nanosuspension might be a useful formulation for improving tretinoin dermal delivery and stability.