Process Development and Robust Control of Physical Attributes of an Amorphous Drug Substance

Control of physical attributes of amorphous active pharmaceutical ingredients (APIs) can be challenging due to processability issues, their wide variation during processing and the requirement to control them to specific ranges. In this article, we report our efforts to develop a robust isolation process for boceprevir, which delivers specific surface areas between 3.0 and 9.4 m²/g. We developed mechanistic process understanding by utilizing a new method to measure glass transition temperature of API suspensions. Boceprevir processability and surface area are determined by the interplay between the suspension operating conditions and glass transition temperature. Processing time and thermal history also influence API surface area evolution, rendering a dynamic nature to it. A control strategy was developed consisting of 2 elements: a continuous tee mixer precipitation process, which delivers API in the 40-60 m²/g range and 1 of 2 annealing step variants. In the first, surface area was controlled in 4 batches to 6.7-7.5 m²/g by equilibrating the API suspension above its glass transition temperature and a subsequent vacuum distillation. The second annealing variant controlled surface area to 4.5-6.5 m²/g for over 70 commercial batches through a dynamic vacuum distillation step with prescribed temperature and % batch volume distilled profiles versus time.     

Addition of Cationic Surfactants to Lipid-Based Formulations of Poorly Water-Soluble Acidic Drugs Alters the Phase Distribution and the Solid-State Form of the Precipitate Upon In Vitro Lipolysis

It has been previously shown that the interaction of some weakly basic drugs with oppositely charged fatty acids during digestion can influence the solid-state form of the drug if it precipitates. The present study hypothesized the opposite effect for weakly acidic drugs. Tolfenamic acid (TA) and an oppositely charged cationic surfactant, didodecyldimethylammonium bromide (DDAB) were combined in a model medium chain lipid formulation. The phase distribution upon in vitro lipolysis was determined using HPLC and the solid-state form of precipitated TA was determined using X-ray diffraction and crossed polarized light microscopy. TA precipitated in a different polymorphic crystalline form to the starting reference material in the absence of DDAB but precipitated in an amorphous form when DDAB was included in the same formulation. The solubility of TA upon dispersion and digestion of the formulation was considerably higher in the presence of DDAB. The findings point to ionic interactions between TA and DDAB as the reason for the improved drug solubility throughout digestion, and precipitation of drug in an amorphous salt form, analogous to what has been observed in the past for some poorly water-soluble weakly basic drugs with anionic co-formers.     

红芪不同提取物对环磷酰胺所致免疫低下小鼠的影响及相关成分含量研究

目的对比研究红芪不同提取物对环磷酰胺(CTX)所致免疫低下小鼠的影响及相关化学成分含量。方法按照体重将昆明种小鼠随机分为空白组、模型组、对照组、醇提物组、水提物组、醇沉物组、残留物组。用CTX 40 mg·kg^-1造成免疫低下模型。对照组灌胃参芪颗粒5 g·kg^-1,其他各组灌胃相应受试样品2 g·kg^-1,正常组和模型组灌胃等量0.9%Na Cl,每天给药1次,连续15 d。称重计算小鼠脏器指数,腹腔注射5%鸡红细胞悬液(CRBC)测定腹腔巨噬细胞吞噬百分率及吞噬指数,用50%二硝基氯苯(DNCB)丙酮溶液致迟发型超敏反应测定OD值,用5%CRBC致敏测定血清溶血素OD值,尾静脉注射印度墨汁测定网状内皮系统吞噬指数及吞噬系数。用UV法测定多糖、总皂苷含量。结果模型组各指标与正常组比较,差异均有统计学意义(均P<0.01)。给药后,正常组、模型组与醇提物组、水提物组、醇沉物组、残留物组的胸腺指数(g·kg^-1)分别为2.55±0.88,1.04±0.74,1.24±0.79,1.81±0.62,1.97±0.83,1.09±0.75,水提物组、醇沉物组与模型组比较,差异均有统计学意义(均P<0.05);水提物组、醇沉物组与残留物组比较,差异均有统计学意义(P<0.05)。这6组的腹腔巨噬细胞吞噬百分率(%)分别为48.58±5.51,28.54±3.15,35.28±6.03,36.99±6.78,39.89±8.33,27.91±8.02,醇提物组、水提物组、醇沉物组的吞噬百分率与模型组比较,差异均有统计学意义(P<0.05或P<0.01);水提物组、醇沉物组与残留物组比较,差异均有统计学意义(P<0.05或P<0.01)。这6组的迟发型超敏反应OD值分别为0.53±0.16,0.23±0.09,0.30±0.10,0.37±0.10,0.36±0.11,0.28±0.14,水提物组、醇沉物组与模型组比较,差异均有统计学意义(P<0.05或P<0.01)。各提取物中多糖和总皂苷含量:醇提物(6.35%;6.57%),水提物(22.64%;7.68%),醇沉物(42.15%;1.86%),残留物(4.33%;5.37%)。结论红芪水提物和醇沉物均能对抗CTX的免疫抑制作用,有一定的增强体液免疫和细胞免疫作用,可增强机体的非特异性免疫和特异性细胞免疫功能。推测多糖是其对抗CTX免疫抑制作用的主要活性部位。     

Continuous production of aqueous suspensions of ultra-fine particles of curcumin using ultrasonically driven mixing device

Abstract

Developing drug formulations for poorly water-soluble drugs is a major challenge for pharmaceutical industries as the poor water solubility limits bioavailability of these drugs. Production of nanoparticles/microparticles of these drugs is one of the ways to improve dissolution rates by increasing interfacial area for dissolution. Curcumin, a compound obtained from the rhizome of curcuma longa (turmeric roots), is a pharmaceutically viable molecule. However, poor aqueous solubility limits its therapeutic use. In this work, we report studies conducted to continuously produce aqueous suspensions of curcumin nano/micro particles. Influence of process parameters such as ultrasound, additives, and solvent to antisolvent ratio on polymorphic outcome and morphology of precipitated particles has been investigated. Ultrasound was found to greatly influence the polymorphic form and the morphology of precipitated particles. Nucleation rates, mixing time, and solid–liquid interfacial energies were also estimated to understand the effect of various processing parameters on the precipitation process.     

An in vitro study of the effect of some dietary components on calculus formation: regulation of calcium phosphate precipitation

OBJECTIVE: We studied the effects of food components on the in vitro formation of calcium phosphate precipitates. MATERIALS AND METHODS: The effects of food components, such as starch, soybean flour, fish meal, rapeseed oil, and coconut oil, on calcium phosphate precipitation were studied using a pH drop method. RESULTS: Although the addition of starch had no effect on the rate of precipitation of amorphous calcium phosphate (ACP), it increased both the rate of transformation of ACP to hydroxyapatite (HAP) and the induction time (i.e. time for the initiation of transformation of ACP to HAP to occur); this was irrespective of the heat treatment of the starch. Amylopectin (insoluble constituent of starch) was effective in increasing the rate of HAP transformation, but amylose (soluble constituent of starch) was not. Oil specimen obtained from rapeseed (400 microl ml(-1)) increased the entire reaction of calcium phosphate precipitation, but that from coconut did not. Protein food, such as soybean flour and fish meal, decreased the rate of transformation of ACP to HAP and increased the induction time, while they had no effect on the rate of ACP precipitation. CONCLUSION: These results suggest that carbohydrate and oil (both are staple diets for the humans) enhance oral calcification (dental calculus formation or re-mineralization of tooth enamel), while side dishes of protein food would decrease it.     

基于决策树算法的热毒宁注射液金银花青蒿醇沉过程质量控制研究

目的基于决策树算法,深入挖掘热毒宁注射液金银花青蒿醇沉过程(金青醇沉)数据并探究潜在生产规律,提升该过程质量控制水平。方法依托数字化中药提取工厂数据平台收集205批金银花和青蒿浸膏(金青浸膏)历史数据并整合成数据矩阵。将数据集随机划分为训练集和测试集后分别采用分类与回归树(classification and regression tree,CART)、随机森林(random forests,RF)和TreeNet算法建立金青醇沉过程模型,比较各模型性能并基于历史数据划分关键变量控制范围。结果 RF和TreeNet模型性能较好且性能接近,综合各模型分析结果得出醇提罐料液比及金银花浓缩收率为重要的影响因素,对重要变量进行依存度分析并优选批次,并以优选批次的金银花分配浸膏质量及加醇量做控制图,密度为1.11 g/cm3的金银花浸膏分配控制范围为557.92～639.62 kg,加醇量的控制范围为3.370～3.828 m3;密度为1.12 g/cm3的金银花浸膏的控制范围为540.4～616.9 kg,加醇量的控制范围为3.317～3.859 m~3。结论决策树算法建立的金青浸膏醇沉过程模型能够有效地挖掘潜在的生产过程规律,为生产过程的质量控制提升提供技术支撑。     

Comparison of phosphotungstate and dextran sulfate-Mg2+ precipitation procedures for determination of high density lipoprotein cholesterol

Because of the controversy over the best method for assaying high density lipoprotein (HDL) cholesterol in the clinical laboratory, a commonly used phosphotungstate method for precipitating low density and very low density lipoproteins (LDL and VLDL) was compared with a recently recommended dextran sulfate precipitation method. The accuracy and precision of HDL cholesterol determinations were similar for both methods. Either of these procedures would appear to be equally satisfactory for the assay of HDL cholesterol in the clinical laboratory.     

正交试验优选复方参芪软胶囊的醇沉工艺

优选复方参芪软胶囊的醇沉工艺。方法：采用正交试验设计,以药液中总多糖的含量和干膏得率为指标,考察浓缩液的相对密度、醇沉浓度、静置时间、醇沉温度对醇沉效果的影响。结果：最佳醇沉工艺为药液浓缩至相对密度1.10,加95％乙醇至含醇量为60％,室温下静置48h。结论：优选的复方参芪软胶囊醇沉工艺简便易行,适用于实际生产配制。     

清脉颗粒醇沉工艺的正交优选

目的：优选清脉颗粒的醇沉工艺。方法：选取药液相对密度,醇沉浓度及醇沉时间为考察因素,以干浸膏得率,薯蓣皂苷元苷含量为考察指标,采用正交试验优选醇沉工艺。结果：优选的醇沉工艺为药液浓缩至相对密度1.13 - 1.18 g·;ml-1,加乙醇至乙醇体积分数为60%,醇沉24 h。结论：优选的工艺稳定可行,为清脉颗粒的临床应用提供试验依据。     

Analytical methodology optimization to estimate the content of non-flavonoid phenolic compounds in Argentine propolis extracts

Context: Traditionally, the content of total phenolics (flavonoid phenolics (FP) and non-flavonoid phenolics (NFP)) and flavonoids (flavone/flavonol and flavonone/dihydroflavonol) in propolis has been determined by different methodologies. Until now, the percentage of total phenolic (TP) compounds that corresponds to FP and NFP, expressed in the same units by a spectrophotometric method, has not been determined.

Objective: The current study proposes a quick and simple methodology that separates FP and NFP in propolis samples and determines TP, FP, and NFP by the same method.

Materials and methods: Propolis samples from five Argentine provinces (Tucumán, Santiago del Estero, Salta, Misiones, and Jujuy) were used. Extraction of TP from the propolis samples was carried out by maceration with 80% ethanol and quantified by Folin–Ciocalteu reagent (FC-R). Then, FP was precipitated with formaldehyde in acid medium. After centrifugation, NFP were determined in the supernatant using FC-R. FP content was calculated as the difference between the content of TP and NFP. The method was also validated using commercial flavonoids and chalcones.

Results: FP recovery in all experiments was between 85.95% and 98.29%. Propolis from Tucumán had significantly higher amounts of total phenols than propolis from other provinces. SE5 showed higher content of FP (81.52%) followed by SA1 (74.75%). The propolis from TUC4, SA4, SE3, and MI showed the lowest FP content and highest content of NFP.

Conclusions: This method provides a simple, reliable, and specific spectrophotometric assay to estimate the content of NFP, FP, and TP in propolis samples.