Tfayli Ali, Piot Olivier, Pitre Franck, Manfait Michel
MeDIAN Unit, CNRS UMR 6142, Faculty of Pharmacy, University of Reims Champagne, Ardenne, France.
Eur Biophys J. 2007 Nov;36(8):1049-58. doi: 10.1007/s00249-007-0191-x. Epub 2007 Jun 13.
Skin is a multilayered organ which covers and protects the surface of human body by providing a barrier function against exogenous agents. Meanwhile, the efficacy of several topically applicated drugs is directly related to their penetration through the skin barrier. Several techniques are commonly used to evaluate the rate, the speed and the depth of penetration of these drugs, but few of them can provide real-time results. Therefore, the use of nondestructive and structurally informative techniques permits a real breakthrough in the investigations on skin penetration at a microscopic scale. Confocal Raman microspectroscopy is a nondestructive and rapid technique which allows information to be obtained from deep layers under the skin surface, giving the possibility of a real-time tracking of the drug in the skin layers. The specific Raman signature of the drug enables its identification in the skin. In this study, we try to follow the penetration of Metronidazole, a drug produced by Galderma as a therapeutic agent for Rosacea treatment, through the skin. The first step was the spectral characterization of Metronidazole in the skin. Then micro-axial profiles were conducted to follow the penetration of the drug in the superficial layers, on excised human skin specimens. For more accurate information, transverse sections were cut from the skin and spectral images were conducted, giving information down to several millimeters deep. Moreover, the collected spectra permit us to follow the structural modifications, induced by the Metronidazole on the skin, by studying the changes in the spectral signature of the skin constituents.
皮肤是一种多层器官，通过提供对外源物质的屏障功能来覆盖和保护人体表面。同时，几种局部应用药物的疗效直接与其透过皮肤屏障的渗透能力有关。通常使用几种技术来评估这些药物的渗透速率、速度和深度，但其中很少能提供实时结果。因此，使用无损且具有结构信息的技术在微观尺度上对皮肤渗透的研究中实现了真正的突破。共聚焦拉曼显微光谱是一种无损且快速的技术，它能够从皮肤表面以下的深层获取信息，从而有可能实时追踪药物在皮肤各层中的情况。药物的特定拉曼特征使其能够在皮肤中被识别。在本研究中，我们试图追踪甲硝唑（一种高德美公司生产的用于治疗酒渣鼻的药物）透过皮肤的渗透情况。第一步是对皮肤中的甲硝唑进行光谱表征。然后在切除的人体皮肤标本上进行微轴剖面分析，以追踪药物在表层的渗透情况。为了获得更准确的信息，从皮肤上切取横断面并进行光谱成像，可提供深入几毫米的信息。此外，通过研究皮肤成分光谱特征的变化，所收集的光谱使我们能够追踪甲硝唑对皮肤引起的结构改变。
