Deng, Zhijian, et al. “Fabrication of Hydrogel Beads Entrappted by Mesoporous Silicates Nanoparticles for PH-Sensitive and Sustained Release of Indomethacin”. Asian Journal of Chemistry, vol. 26, no. 12, June 2014, pp. 3609-14, doi:10.14233/ajchem.2014.16613.