Hierarchically mesoporous silica nanoparticles: extraction, amino-functionalization, and their multipurpose potentials.

Hierarchically mesoporous silica nanoparticles (HMSNs) with uniform morphology and structure and with a diameter of ca. 100-220 nm were facilely fabricated using water, ethanol and ethyl ether as cosolvents. Template extraction and amino-functionalization were performed toward the HMSNs. These hierarchical mesopores are supposed to possess more advantages than conventional monomodal mesopores. Amino-functionalized HMSNs were homogeneously grafted with fluorescent molecules and loaded with Au nanoparticles (NPs), respectively. The extracted HMSNs were also successfully used to construct antireflection and superhydrophilc coatings. Drug release experiments showed that HMSNs exhibit much quicker rates of drug release compared with conventional mesoporous NPs due to their hierarchically mesoporous structures.