Contents: (Small 11/2011)

Drug DeliveryThe cover picture shows magnetically doped mesoporous silica nanoparticles (MSNs) being fi rst internalized by a cell (top) and adsorbing intracellular molecules (green).The particles are then exocytosed from the cell.Afterwards the ejected particles are either retrieved with a magnet to harvest the sequestered proteins, or taken up by a neighboring cell, which, if cancerous, could be less prone to exocytose the MSNs.These results suggest that complex targeting groups might not be necessary in the use of nanoparticles to treat cancer, and they may open a new avenue for the use of nanoparticles as tools to harvest proteins and biomolecules from living cells.For more information, please read the Communication "Exocytosis of Mesoporous Silica Nanoparticles from Mammalian Cells: From Asymmetric Cell-to-Cell Transfer to Protein Harvesting" by I. I.