Fractal and polarization analysis of diffusively scattered light is applied to determine the complex relationship between fractal dimension of structural morphology and concentration of chemically active ingredients in two pharmaceutical mixture systems including a series of binary mixtures of acetaminophen in lactose and three multicomponent blends with a proprietary active ingredient. A robust approach is proposed to identify and filter out multiple- and single-scattering components of scattering indicatrix. The fractal dimension extracted from scattering field reveals complex structural details of the sample, showing strong dependence on low-dose drug concentration in the blend. Low-angle diffraction shows optical “halo” patterns near the angle of specular reflection caused by light refraction in microcrystalline aggregates. Angular measurements of diffuse reflection demonstrate noticeable dependence of Brewster's angle on drug concentration. It is shown that the acetaminophen microcrystals produce scattered light depolarization due to their optical birefringence. The light scattering measurement protocol developed for diffusively scattered light by microcrystalline pharmaceutical compositions provides a novel approach for the pattern recognition, analysis and classification of materials with a low concentration of active chemical ingredients.

中文翻译：

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使用微晶药物聚集体的光散射的分形和偏振特性

应用漫散射光的分形和偏振分析来确定两种药物混合物系统中结构形态的分形维数与化学活性成分浓度之间的复杂关系，包括一系列对乙酰氨基酚在乳糖中的二元混合物和三种具有专有活性的多组分混合物成分。提出了一种鲁棒的方法来识别和滤除散射指标的多重和单一散射分量。从散射场提取的分形维数揭示了样品的复杂结构细节，显示出对混合物中低剂量药物浓度的强烈依赖性。低角度衍射显示在微晶聚集体中由光折射引起的镜面反射角附近的光学“光晕”图案。漫反射的角度测量表明布鲁斯特角对药物浓度的显着依赖性。结果表明，对乙酰氨基酚微晶由于其光学双折射而产生散射光去偏振。为微晶药物组合物的漫散射光开发的光散射测量协议为具有低浓度活性化学成分的材料的模式识别、分析和分类提供了一种新方法。