Liquid extraction surface analysis to study drug distribution in brain

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Information about drug distribution after intake in a certain tissue is of relevance as it provides useful information for the development of novel medicines. Conventional homogenization methods are not applicable in this context as they provide a qualitative information about the drug present in the analyzed samples. However, data about the spatial distribution and the ability of the drug to cross the cellular barrier is usually missing. To overcome this drawback, Swales and coworkers have studied the drug distribution in brain tissue using liquid extraction surface analysis combined to mass spectrometry (LESA-MS). LESA-MS is a surface sampling technique that combines liquid extraction from the surface of tissue sections with mass spectrometry.

The authors use mass spectrometric imaging (MSI) to build an image of xenobiotic and endogenous compound distribution to asses drug brain barrier penetration. LESA-MSI was useful to obtain the map distribution of poorly penetrative compounds in contrast to MALDI-MSI which was most appropriate to obtain the distribution of penetrative compounds. Therefore, both techniques should be jointly used to obtain a complete profile of drug distribution.

This research opens a door in this application field where, as it is said by the authors, there is still too much work to be done.

References
(1) Mapping Drug Distribution in Brain Tissue Using Liquid Extraction Surface Analysis Mass Spectrometry Imaging. Link to the article
Related posts
(1) Mass spectrometric analysis of surfaces by electro-focusing liquid extractive surface analysis. Link to the post


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