Autonomous in vitro anticancer drug release from mesoporous silica nanoparticles by pH-sensitive nanovalves.

Abstract

Mesoporous silica nanoparticles (MSNP) have proven to be an extremely effective solid support

for controlled drug delivery on account of the fact that their surfaces can be easily functionalized in order

to control the nanopore openings. We have described recently a series of mechanized silica nanoparticles,

which, under abiotic conditions, are capable of delivering cargo molecules employing a series of nanovalves.

The key question for these systems has now become whether they can be adapted for biological use

through controlled nanovalve opening in cells. Herein, we report a novel MSNP delivery system capable

of drug delivery based on the function of -cyclodextrin ( -CD) nanovalves that are responsive to the

endosomal acidification conditions in human differentiated myeloid (THP-1) and squamous carcinoma (KB-

31) cell lines. Furthermore, we demonstrate how to optimize the surface functionalization of the MSNP so

as to provide a platform for the effective and rapid doxorubicin release to the nuclei of KB-31 cells.