UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK.
Adv Drug Deliv Rev. 2012 Apr;64(5):431-9. doi: 10.1016/j.addr.2011.11.001. Epub 2011 Nov 6.
Many processing steps can result in generation of partially amorphous materials. While the fraction of disorder may be low (typically up to 5% w/w) its location primarily on particle surfaces means its effects might be significant, especially in regard to powder flow and force of adhesion. Quantification of small amorphous contents is thus becoming an important part of product development. Isothermal microcalorimetry can be used as an assay for amorphous content by controlling the relative humidity or relative vapour pressure in the sample ampoule. The technique is very sensitive (typically detecting less than 1% w/w amorphous content) and universally applicable to pharmaceutical powders. However method design and data interpretation are critical factors in successful assay design. This article discusses methods and techniques and reviews current pharmaceutical applications to aid assay design.
许多处理步骤可能导致部分非晶态材料的生成。虽然无序的比例可能较低（通常最多为 5%w/w），但其主要位于颗粒表面，这意味着其影响可能很大，尤其是在粉末流动和附着力方面。因此，定量检测小的非晶态含量正在成为产品开发的一个重要部分。通过控制样品小瓶中的相对湿度或相对蒸气压，等温微量热法可用作非晶态含量的测定方法。该技术非常灵敏（通常检测不到 1%w/w 的非晶态含量），适用于所有药物粉末。然而，方法设计和数据解释是非晶态含量测定成功的关键因素。本文讨论了方法和技术，并回顾了当前药物应用，以帮助测定设计。
