Activery Biotech, Carrer Portugal 33/35, 08290 Cerdanyola del Vallès, Spain.
Int J Pharm. 2012 Jan 17;422(1-2):271-9. doi: 10.1016/j.ijpharm.2011.11.009. Epub 2011 Nov 15.
Optimum experimental parameters for modulated differential scanning calorimetry were determined using a design of experiments approach. Two different strategies were tested, an isothermal method only varying modulation period and amplitude and a non-isothermal method including an underlying linear heating ramp. Three different test compounds were investigated including a blank of NaCl, a small pharmaceutically active molecule (Valsartan) and a polymer (PVP-VA 64). Obtained optimum values were found to be identical for each compound tested and shown to be statistically robust for repeated daily experimentation. Optimized signals showed lower glass transition values T(g) paired with higher changes in isobaric heat capacity Δc(p). Measured glass transition signals exhibited minimal variation during repeat analysis, and showed significantly better signal-to-noise ratios in comparison to literature data.
采用实验设计方法确定调制差示扫描量热法的最佳实验参数。测试了两种不同的策略,一种是仅改变调制周期和幅度的等温方法,另一种是包括基础线性加热斜坡的非等温方法。研究了三种不同的测试化合物,包括 NaCl 空白、一种小的药物活性分子(缬沙坦)和一种聚合物(PVP-VA64)。发现对于每种测试的化合物,获得的最佳值是相同的,并且对于重复的日常实验是统计上稳健的。优化后的信号显示出较低的玻璃化转变值 T(g),并伴随着等压热容变化 Δc(p)的升高。在重复分析过程中,测量的玻璃化转变信号表现出最小的变化,并且与文献数据相比,具有显著更好的信噪比。