Spatial resolution of transdermal water mobility using NMR microscopy.

High resolution images were obtained using high-field nuclear magnetic resonance microscopy of in vitro preparations of hydrated hairless rat skin. The major anatomical features observed were comparable to those seen by electron microscopy and include the stratum corneum, the viable epidermis, sebaceous glands, the cell layers surrounding hair follicles (the outer and inner root sheaths), and regions of subcutaneous fatty deposits. Calculated diffusion maps demonstrated that signal intensity is sufficient to obtain quantitative water mobility data from the viable epidermis and the hair follicle/sebaceous gland regions. Images from skin immersed in D2O clearly distinguish signal contributions that arise from fat from those which arise from water, and indicate that the calculated diffusion maps include only proton mobility from water in skin. These results may lead to further applications for using quantitative nuclear magnetic resonance microscopy for examining transdermal transport processes of in vitro skin preparations.