Research Article Effect of Multimodal Pore Channels on Cargo Release from Mesoporous Silica Nanoparticles Sushilkumar A. Jadhav, 1,2 Valentina Brunella, 1,2 Gloria Berlier, 1,2 Elena Ugazio, 2,3 and Dominique Scalarone 1,2 1 Department of Chemistry, University of Torino, 10125 Torino, Italy 2 NIS Research Centre, University of Torino, 10125 Torino, Italy 3 Department of Pharmaceutical Science and Technology, University of Torino, 10125 Torino, Italy Correspondence should be addressed to Sushilkumar A. Jadhav; sushil.unige@gmail.com and Dominique Scalarone; dominique.scalarone@unito.it Received 30 January 2016; Revised 11 May 2016; Accepted 12 May 2016 Academic Editor: Andrea Falqui Copyright © 2016 Sushilkumar A. Jadhav et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Mesoporous silica nanoparticles (MSNs) with multimodal pore channels were fully characterized by TEM, nitrogen adsorption- desorption, and DLS analyses. MSNs with average diameter of 200 nm with dual pore channel zones with pore diameters of 1.3–2.6 and 4 nm were tested for their use in drug delivery application. Important role of the multimodal pore systems present on MSNs on the quantitative release of model drug ibuprofen was investigated. Te results obtained revealed that the release profle for ibuprofen clearly shows distinct zones which can be attributed to the respective porous channel zones present on the particles. Te fuctuations in the concentration of ibuprofen during the prolonged release from MSNs were caused by the multimodal pore channel systems. 1. Introduction Mesoporous silica nanoparticles (MSNs) represent one of the most versatile reservoir materials used for delivery of diferent molecules. Te versatility comes from stability, biocompatibility, highly ordered porosity, and large surface area of this material [1]. In particular MSNs have shown great promise in their use for drug delivery [2–4], targeted drug delivery [5], improved solubility and delivery of poorly solu- ble drugs [6], pH responsive drug delivery systems [7], and controlled release of drugs [8]. In all these applications MSNs can be used as reservoir for drug molecules, and prolonged and controlled release of the drug in diferent media can be obtained by difusion. Several molecules from diferent classes of drugs such as anti-infammatory, anticancer drugs, and antioxidants were loaded inside MSNs and their release kinetics was studied [9, 10]. Te extended studies have revealed that there are several factors which infuence drug loading, stability of the material, and drug release. Altogether these factors determine the efciency of MSNs in the delivery of the desired drugs in diferent environments. Te most commonly investigated factors which greatly infuence the delivery of molecules are size of the particles and porosity [11, 12], pore length, pore volume and pore diameter [13], morphology [14], pore size [15], and loading capacity and their hydrothermal stability [16]. Improved control over the release of the drugs which allows tuning of the release profles can be achieved by trigger mechanisms activated by various organic functional groups or smart polymers grafed on the porous particles [17]. However fewer investigations are reported which go into the details of the orientations of the microstructures which are multimodal pore systems that may get formed during the synthesis of MSNs. In last few years several optimized hydrothermal or sol-gel synthesis methods for the synthesis of MSNs, which yield monodis- perse particles with improved control over the obtained porosity, pore length or pore volume, and orientations of the mesochannels, have been reported [18, 19]. Various factors such as the use of core swelling (pore extending) agents together with the traditional micelle forming agents, the choice of the alkoxysilane itself, which undergoes hydrolysis- condensation reaction to give rise to the siloxane network, Hindawi Publishing Corporation Journal of Nanomaterials Volume 2016, Article ID 1325174, 7 pages http://dx.doi.org/10.1155/2016/1325174