Nanoparticle vaccines Yu 201412 Nov 2018 20:30
One of the most promising inorganic materials for nanovaccinol-ogy and delivery system design is silica. Silica-based nanoparticles(SiNPs) are biocompatible and have excellent properties asnanocarriers for various applications, such as selective tumortargeting [72], real-time multimodal imaging [73], and vaccinedelivery. The SiNPs can be prepared with tunable structural param-eters. By controlling the sol–gel chemistry, the particle size andshape of SiNPs can be adjusted to selectively alter their inter-action with cells [74]. The abundant surface silanol groups arebeneficial for further modification to introduce additional function-ality, such as cell recognition, absorption of specific biomolecules,improvement of interaction with cells, and enhancement of cellu-lar uptake [75–78]. In addition, porous SiNPs such as mesoporoussilica nanoparticles (MSNs) and hollow SiNPs can be prepared bytemplating methods, which can be applied as a multifunctionalplatform to simultaneously deliver cargo molecules with variousmolecular weights [74]. MSNs with sizes in the range of 50–200 nmhave been studied as both nano-carriers and adjuvants for deliveryof effective antigens [79–81], such as those derived from porcinecircovirus [82] and HIV [83]. MSNs can be used to control the releaseof antigens by controlling the shape, pore size and surface func-tionalization [79,84]. Compared to solid SiNPs, MSNs have higherloading capacity for their larger specific surface area, and betterperformance in delivery and controlled release due to the tun-able hollow and mesoporous structure. In addition, MSNs can bedegraded which can then be excreted in the urine [85–87]. Withthese properties, MSNs show potential to become high-efficiency,controlled-release nano-carriers in future vaccine formulations