@article {17774, title = {Sustained release of prednisone and mesalamine from diatom exoskeletons: bioinspiration for the development of safe oral drug delivery devices to tackle gastrointestinal diseases}, journal = {TERM STEM 2013: Nanotechnology as a Tool for Improving Tissue Engineering and Regenerative Medicine}, year = {2013}, month = {2013-10-10 00:00:00}, address = {Porto, Portugal}, abstract = {

Mesoporous silicon and silica-based particles have recently been synthesized and proposed for the controlled delivery of several drugs [1,2]. On the other hand, nature and in particular marine organisms have been the source and inspiration for the development of different biomedical applications, including drug delivery devices [3]. On the border of both rests diatoms exoskeletons, nature-made porous silica-based microparticles with amazing morphological features, promising a high potential in drug delivery. Nevertheless, its safety and drug permeability on oral formulations have not yet been studied. In this study, we have demonstrated that diatoms silica microparticles (DSM) have almost no toxicity in colon cancer cells Caco-2, HT-29, HCT-116 and Caco-2/HT-29, even at concentrations as high as 1000 {\textmu}g/mL. Moreover, the delivery profile of two common drugs to address gastrointestinal diseases, mesalamine (anti-inflammatory) and prednisone (glucocorticosteroid). DSMs are able to release prednisone in a controlled manner and change its absorption pattern, which may improve the safety of its administration. In addition, DSMs can enhance the permeation of mesalamine. These results confirm the potential of DSMs for the development of oral formulations for the therapy of gastrointestinal diseases.

[1] Santos HA, Bimbo LM, Lehto VP, Airaksinen AJ, Salonen J, Hirvonen J, {\textquotedblleft}Multifunctional porous silicon for therapeutic drug delivery and imaging{\textquotedblright}, Current Drug Discovery Technologies 8 (2011), 228-249.

[2] Limnell L, Santos HA, M{\"a}kil{\"a} E, Heikkil{\"a} T, Salonen J, Murzin DY, Kumar N, Laaksonen T, Peltonen L, Hirvonen J, {\textquotedblleft}Drug delivery formulations of ordered and non-ordered mesoporous silica: comparison of three drug loading methods{\textquotedblright}, Journal of Pharmaceutical Science 100 (2011), 3294-3306.

[3] Silva TH, Alves A, Ferreira BM, Oliveira JM, Reys LL, Ferreira RF, Sousa RA, Silva SS, Mano JF, Reis RL, "Materials of marine origin: a review on polymers and ceramics of biomedical interest", International Materials Reviews, 57 (2012), 276-306.

}, keywords = {diatoms, Drug delivery, Sustained release}, author = {Zhang, H. and Shahbazi, M. - A. and M{\"a}kil{\"a}, E. and Silva, T. H. and Reis, R. L. and Salonen, J. J. and Hirvonen, J. and Santos, H. A.} }