A mesoporous silica particle having 10 mole % to 65 mole % amine groups present in the silica of the particle and on the silica surface of the particle. The particle has Pm 3n symmetry and a size of 25 nm to 500 nm. Methods of making such particles from the low temperature reaction of silane precursor and amino silane precursors is provided. The particle can be used in applications such as imaging, drug delivery, catalysis, and CO.sub.2 sequestration.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
 This invention was made with government support under grant no. DMR-0611430 and DMR-1120296 awarded by the National Science Foundation, grant no. DE-FG02-97ER62443 awarded by the Department of Energy, grant no. R21DE018335 awarded by the National Institute of Dental and Craniofacial Research, and Cooperative Agreement Number 2009-ST-108-LR0004 with the U.S. Department of Homeland Security. The Government has certain rights in the invention.