The systems containing clays and clay minerals from modified drug release: a review.

Rodrigues LA1, Figueiras A, Veiga F, de Freitas RM, Nunes LC, da Silva Filho EC, da Silva Leite CM
Colloids Surf B Biointerfaces. 2013 Mar 1;103:642-51. doi: 10.1016/j.colsurfb.2012.10.068. Epub 2012 Nov 20

https://www.ncbi.nlm.nih.gov/pubmed/23253474