Mesoporous silica nanoparticles (MSNs) provide a non-invasive and biocompatible delivery platform for a broad range of applications in therapeutics, pharmaceuticals and diagnosis. The creation of smart, stimuli-responsive systems that respond to subtle changes in the local cellular environment are likely to yield long term solutions to many of the current drug/gene/DNA/RNA delivery problems. In addition, MSNs have proven to be promising supports for enzyme immobilisation, enabling the enzymes to retain their activity, affording them greater potential for wide applications in biocatalysis and energy. This review provides a comprehensive summary of the advances made in the last decade and a future outlook on possible applications of MSNs as nanocontainers for storage and delivery of biomolecules. We discuss some of the important factors affecting the adsorption and release of biomolecules in MSNs and review of the cytotoxicity aspects of such nanomaterials. The review also highlights some promising work on enzyme immobilisation using mesoporous silica nanoparticles.

Multi-shelled mesoporous silica hollow nanospheres (MMSHNs) with uniform size distribution (∼150 nm), tuneable shell thickness (7–20 nm) and layer number (1–4 layers) have been successfully synthesized through a facile vesicle template approach derived from a self-assembly of surfactants [C₃F₇O(CFCF₃CF₂O)₂CFCF₃CONH(CH₂)₃N⁺(C₂H₅)₂CH₃I⁻] (FC4) and EO₁₀₆PO₇₀EO₁₀₆ (F127). The formation of these hollow nanospheres was monitored by dynamic light scattering. A vesicle template mechanism for the molecular build-up of these silica hollow nanospheres was proposed based on the dynamic light scattering data in combination with material characterizations including transmission electron microscopy (TEM), scanning electron microscopy (SEM) and nitrogen sorption analysis. Through this method, CdTe quantum dots (QDs) were in situ encapsulated into the hollow nanospheres. These hollow nanospheres demonstrated a good selective adsorption capacity for Methylene Blue dye, and can effectively load drug molecules for delivery. It is expected these hollow nanospheres have great potential for the application in fluorescence biological probes, bio-imaging, drug delivery and water purification.