Hanh B D, Neubert R H, Wartewig S, Christ A, Hentzsch C
Martin-Luther-University, School of Pharmacy, Institute of Pharmaceutics and Biopharmaceutics, Wolfgang-Langenbeck-Str. 4, D-06120 Halle/Saale, Germany.
J Pharm Sci. 2000 Sep;89(9):1106-13. doi: 10.1002/1520-6017(200009)89:9<1106::aid-jps2>3.0.co;2-j.
The penetration of the drugs dithranol and methoxsalen from semisolid Vaseline formulation into an artificial dodecanol-collodion membrane was followed by three spectroscopic methods; they are, step-scan Fourier transform infrared (FTIR) photoacoustic spectroscopy (PAS) with phase modulation, FTIR-attenuated total reflection (FTIR-ATR), and ultraviolet (UV) PAS. The uptake of the drug in the membrane was quantified by monitoring the dependence of an appropriate drug band on the penetration time. The PAS experiments were carried out with various modulation frequencies for generating various sampling depths. Based on Fick's second law, the diffusion coefficient was derived by numerical fitting of the experimental data. It appears that the diffusion coefficient for the drug in the membrane depends on the distance. The comparative studies demonstrate that FTIR-ATR is favored for permeation studies, whereas the PAS techniques are capable of providing the drug penetration profile in the membrane. Thus, extended experimental data are available for new insight into the penetration process. However, because of the photacoustic cells at hand, PAS is only suitable for in vitro studies.
采用三种光谱方法跟踪了药物地蒽酚和甲氧沙林从半固体凡士林制剂渗透到人工十二醇 - 火棉胶膜中的过程；这三种方法分别是：具有相位调制的步进扫描傅里叶变换红外（FTIR）光声光谱法（PAS）、FTIR衰减全反射法（FTIR - ATR）以及紫外（UV）光声光谱法。通过监测合适的药物谱带对渗透时间的依赖性来定量膜中药物的摄取量。进行光声光谱实验时采用了各种调制频率以产生不同的采样深度。基于菲克第二定律，通过对实验数据进行数值拟合得出扩散系数。结果表明，药物在膜中的扩散系数取决于距离。对比研究表明，FTIR - ATR更适合用于渗透研究，而光声光谱技术能够提供药物在膜中的渗透曲线。因此，有了扩展的实验数据，可对渗透过程有新的认识。然而，由于现有的光声池，光声光谱法仅适用于体外研究。
