Aminated hollow mesoporous silica nanoparticles as an enhanced loading and sustained releasing carrier for doxorubicin delivery

Mesoporous silica nanoparticles (MSN) have been known as potential delivery system for doxorubicin (DOX). However, they have restricted applications due to their uncontrolled leakage, burst release of open pores and limited loading content of non-hollow core. In this study, a simple and effective system based on hollow MSN (HMSN) was synthesized and amino functionalized in order to optimize loading capacity and improve release profile for DOX delivery. HMSN were prepared following sSiO(2) hard template preparation, mesoporous silica layer coating, and core template etching. Then the nanoparticles were aminated by (3-aminopropyl)-triethoxysilane (APTES) at different concentrations. Successful amino functionalization was shown by FT-IR, XPS and TGA. Surface area was revealed by BET and surface charge was determined by Zeta potential. TEM images showed high uniformity of spheres with hollow core-mesopomus shell structure and 154.0 +/- 0.9 nm diameter of the aminated HMSN (HMSN-NH2), whilst the optimal -NH2 amount on the aminated HMSN surface was found to be 80.17 mu g/100 mg by Kaiser test. After being aminated, HMSN-NH2 performed 3.63-fold increase in DOX loading content and 1.50-fold decrease in cumulative DOX release after 48 h. Additionally, MTT assays indicated that HMSN-NH2 was a biocompatible nanocarrier which had no toxicity on human hepatocellular carcinoma J5 (HCC J5) cells. The results suggested that the synthesized HMSN-NH2 could be a great potential nanocarrier in cancer therapy with optimal loading content and sustained release of DOX.