Microencapsulation by Emulsion Non-Solvent Additicin Method

Abstract

Cellulose acetate butyrate microcapsules containing propranolol were prepared by emulsion non-solvent addition method. The effects on drug release of different polyethylene glycols (PEG), various concentrations of PEG 4000, and particle size of the drug to be encapsulated were investigated. In vitro dissolution of microcapsules in simulated intestinal fluid and buffers at different pH was also studied. PEGs were found to increase drug release for this system. The pH dissolution profiles of the microcapsules indicated that dissolution was slightly pH dependent during the first 8 hours of dissolution.     

Microencapsulation of Vitamin B-12 by Emulsion Technique

Stability of vitamin B-12 and its uniform mixing in multivitamin solid dosage forms was attempted to increase by microencapsulating the vitamin by emulsion technique. The prepared products were evaluated for their strength, dissolution rate, and size distribution and compared for the biological stability with various other forms of vitamin B-12. The technique and adopted method were realised to be feasible and therefore, attempts were made for scaling up the procedure to manufacturing scale.     

乳浊液法制备超细氧化锆粉体

用乳浊液法制备了平均晶粒尺寸为１３～１４ｎｍ，二次颗粒呈多边形或球形的３ｍｏｌ％Ｙ２Ｏ３－ＺｒＯ２粉体。运用Ｘ射线衍射、Ｘ荧光光谱、电感耦合等离子体光谱、比表面仪、透射电镜以及差热－热失重仪等分析手段对粉体进行了表征。实验还表明，制备过程中所采用的非均相共沸蒸馏法是一种排除凝胶中残留水份的有效手段，从而使得合成粉体中的团聚现象得到控制。     

Methoxybutropate Microencapsulation by Gelatin-Acacia Complex Coacervation

Microcapsules of methoxybutropate solid particles or of an oily saturated solution of the same drug were prepared by complex coacervation between gelatin and acacia and dried with three different methods: isopropanol addition, spray-drying, and freeze-drying. Successively, microparticles were analyzed by infrared thermobalance, ultraviolet (UV) spectroscopy, optical and scanning electron microscopy, and sieves to find out parameters such as yield, moisture content, encapsulation percentage, morphology of solid particles, and particle size. Results highlighted that the most appropriate drying method for industrial purposes was spray-drying, particularly for oil-containing microcapsule formulations.     

Gelatin-Acacia Complex Coacervation as a Method for Ketoprofen Microencapsulation

Abstract

Ketoprofen microcapsules were prepared by complex coacervation between gelatin and acacia, and dried with different methods: isopropanol addition, spray-drying, and freeze-drying, Successively, microparticles were analyzed by infrared thembalance, ultraviolet spectroscopy, optical and scanning electron microscopy, and sieves; and subjected to dissolution studies in order to examine parameters such as yield, moisture content, encapsulation percentage, morphology of solid particles, particle size, and dissolution behavior. Provided that encapsulation and drying methods did not affect ketoprofen dissolution profiles, the most appropriate drying method for industrial purposes was spray-drying.     

Gelatin-Acacia Complex Coacervation as a Method for Ketoprofen Microencapsulation

Ketoprofen microcapsules were prepared by complex coacervation between gelatin and acacia, and dried with different methods: isopropanol addition, spray-drying, and freeze-drying, Successively, microparticles were analyzed by infrared thembalance, ultraviolet spectroscopy, optical and scanning electron microscopy, and sieves; and subjected to dissolution studies in order to examine parameters such as yield, moisture content, encapsulation percentage, morphology of solid particles, particle size, and dissolution behavior. Provided that encapsulation and drying methods did not affect ketoprofen dissolution profiles, the most appropriate drying method for industrial purposes was spray-drying.     

卡尔·费休法测定乳化炸药含水量

文章对乳化炸药中水分的存在形式进行了分析,并提出了一种适用于乳化炸药含水量的测定方法——卡尔·费休水分测定法。经过测定不同生产工艺、不同乳化剂的乳化炸药样品的含水量,并作重现性试验和回收试验,表明该方法在测量乳化炸药含水量时,具有测量时间短、精度高、测量结果重现性好等特点,适合在生产线或实验室进行推广应用。     

用正交试验方法优化乳化炸药设计

文章运用了正交试验设计的方法,对乳化炸药的配方进行优化设计。通过＂正交表＂来选择试验条件,利用正交表的特点进行数据分析,从而通过代表性很强的少数次试验摸清各因素对结果的影响情况,并根据影响的大小确定因素主次顺序,找出较好的生产条件或较优的参数组合。试验结果表明,影响乳化炸药作功能力的因素有原材料配比、乳化剂类型、敏化方式,而原材料配比是影响乳化炸药作功能力的关键因素,乳化剂类型是主要因素,敏化方式是次要因素。     

乳化交联法制备聚乙烯醇微球的工艺研究

采用乳化交联法,以含有表面活性剂的植物油为连续相(油相),聚乙烯醇(PVA)水溶液为分散相(水相),戊二醛为交联剂,盐酸为催化剂,制备了PVA微球.利用FT-IR、SEM及粒度分析仪等设备对微球的组成、形貌及粒径分布进行了测试,并考察了几种关键工艺参数对微球制备的影响.结果表明,在PVA溶液浓度为5％,表面活性剂采用2 g脱水山梨醇单油酸酯(Span 80),乳化温度为50℃,1mol/L稀盐酸催化戊二醛交联的条件下,可以获得球形规整、表面光滑且分散性好的PVA微球.粒径分析结果显示,所得PVA微球的平均粒径约为25 μm,且分布在15～45 μm范围内的微球约占其总量的80％.     

消光法乳剂颗粒粒径测量中浓度影响分析

为了研究消光法颗粒粒径测量过程中浓度对测量结果的影响,根据Lambert-Beer定律,对不同浓度下的乳剂采用多波长消光法进行测量分析,同时采用蒙特卡罗法进行数值模拟分析。实验和数值结果均表明:浓度对消光法测试结果的影响效果存在一个临界浓度范围。对于脂肪乳剂,该临界浓度出现在质量分数1.8‰左右;对于橄榄油乳剂,临界浓度则出现在0.5‰～0.6‰之间。超过该范围后,测量的粒径将受浓度变化剧烈影响。     

一种检测乳化炸药及其基质密度的简便方法

文章在分析常用乳化炸药、乳化炸药基质密度测定方法的基础上,提出了一种基于阿基米德定律检测乳化炸药及其基质密度的方法及仪器。使用该方法及仪器可以大大缩短检测周期和提高检测结果的准确度。经测试和比较,乳化基质密度检测周期可由原来的358s缩短至20s,检测结果的绝对误差和均方值由原来的0．0019g/cm3、6．50E。降低至0．0005g／cm3、3．82E-6,应用这种方法和仪器还可以提高工作效率、减少工作量和生产线工作定员。     

乳化炸药作功能力的估算方法

文中以炸药理论为基础，根据检测数据建立了乳化炸药的作功能力与爆速之间的基本关系式，并归纳了具体作功能力的计算方法。     

柱面式光栅超微粒乳剂的涂布方法

讨论了柱面式光栅的超微粒乳剂涂布问题；提出了一种有效的涂布方法──动态柱面旋转定量涂布法，并取得了理想的实用效果。     

The Development of a Solarized Image in a Non-Solvent Physical Developer

It is shown that in the solanzation region more image is developable in a non-solvent physical developer than in a non-solvent chemical developer.     

电导率法检测乳化炸药储存稳定性的实验研究

采用破乳剂Tween80,在温度70℃、搅拌速度400 r/min的条件下将乳化基质、乳化炸药在400 mL的水溶液中进行破乳。检测破乳过程中水溶液的电导率变化,绘制电导率-时间曲线,以此判断乳化基质、乳化炸药储存期间的稳定性。论述了实验原理及影响实验的因素。实际检测了乳化基质和乳化炸药在自然储存及冷冻储存条件下电导率-时间曲线的变化规律。检测结果与显微镜观察破乳情况和实际爆破性能对比表明,电导率法检测得到的结论与显微镜观察的析晶破乳状态及实际爆破性能基本一致。最终,通过大量的生产线检测数据确定了一组电导率-时间曲线作为标准曲线,以此为依据可快速判断乳化炸药的储存期。     

Synthesis of Poly(DL-Lactide-Co-Glycolide) Nanoparticles with Entrapped Magnetite by Emulsion Evaporation Method

The goal of this study was to synthesize Poly(DL-lactide-Co-glycolide) nanoparticles with entrapped magnetite, of under 100 nm in diameter, for future drug delivery applications. The emulsion evaporation method was selected to form poly(lactide-co-glycolide) (PLGA) nanoparticles with entrapped magnetite (Fe₃O₄) in the polymeric matrix, in the presence of sodium dodecyl sulfate (SDS) as a surfactant. Magnetite, a water-soluble compound, was surface functionalized with oleic acid to ensure its efficient entrapment in the PLGA matrix. The inclusion of magnetite with oleic acid (MOA) into the PLGA nanoparticles was accomplished in the organic phase. Synthesis was followed by dialysis, performed to eliminate the excess SDS, and lyophilization. The synthesized nanoparticles ranged in size from 38.6 to 67.1 nm for naked PLGA nanospheres and from 78.8 to 87.2 nm for MOA-entrapped PLGA nanospheres. The entrapment efficiency ranged from 57.36% to 77.3%.     

Synthesis of Poly(DL-Lactide-Co-Glycolide) Nanoparticles with Entrapped Magnetite by Emulsion Evaporation Method

The goal of this study was to synthesize Poly(DL-lactide-Co-glycolide) nanoparticles with entrapped magnetite, of under 100 nm in diameter, for future drug delivery applications. The emulsion evaporation method was selected to form poly(lactide-co-glycolide) (PLGA) nanoparticles with entrapped magnetite (Fe₃O₄) in the polymeric matrix, in the presence of sodium dodecyl sulfate (SDS) as a surfactant. Magnetite, a water-soluble compound, was surface functionalized with oleic acid to ensure its efficient entrapment in the PLGA matrix. The inclusion of magnetite with oleic acid (MOA) into the PLGA nanoparticles was accomplished in the organic phase. Synthesis was followed by dialysis, performed to eliminate the excess SDS, and lyophilization. The synthesized nanoparticles ranged in size from 38.6 to 67.1 nm for naked PLGA nanospheres and from 78.8 to 87.2 nm for MOA-entrapped PLGA nanospheres. The entrapment efficiency ranged from 57.36% to 77.3%.     

乳化机爆炸事故后果定量分析的探讨

文章采用定量分析的方法对乳化机等危险设备模拟爆炸后,冲击波和破片可能产生的危害进行了探讨,给出了Δp-r和E-x曲线图.乳化机等危险设备爆炸后冲击波的伤害范围比较小,爆炸破片的伤害范围比较大,因此加强对爆炸后的破片防护是减少人员伤亡的主要途径.     

乳化炸药稳定性测试方法研究

采用高低温循环试验测试样品的爆速值、电导率和硝酸铵析出量,综合分析各测试方法的结果来评估乳化炸药的稳定性,并设计了实验原理图。实验研究表明:随着高低温循环次数的增加,乳化炸药的爆炸性能逐渐下降,电导率和AN析出量逐渐增加,且呈现相类似的变化趋势。18次高低温循环后电导率增加更显著,当循环次数在18～30次内,破乳现象加剧,且乳化炸药的爆速逐渐降低,在27次循环后乳化炸药发生拒爆;将常温下爆速与高低温循环的爆速对比,得到高低温循环次数对应的自然存储天数,如高低温循环5次相当于自然存储76.6 d。