Multifunctional Mesoporous Silica Nanoprobes: Material Chemistry–Based Fabrication and Bio‐Imaging Functionality

Nanoparticles‐based bioimaging probes are attracting broad attention for various biomedical applications. As one of the mostly explored nanoplatforms, mesoporous silica nanoparticles (MSNs) show high clinical‐translation potential for diagnostic probing/imaging. Based on their tunable morphology, abundant surface chemistry, and well‐defined mesostructure, MSNs are regarded as the desirable platforms for constructing diverse nanoprobes via incorporation of a variety of functional moieties or components. In this review, the authors summarize and discuss recent progress in the rational design and fabrication of multifunctional mesoporous silica‐based composite nanoprobes for versatile bioimaging applications. Four kinds of methodologies for the fabrication of these mesoporous silica‐based nanoprobes are discussed, including encapsulating functional nanoparticles within a mesoporous silica shell, assembling functional nanoparticles on the surface of MSNs, dispersing nanoparticles into the nanometer‐scale mesopores of MSNs, and doping functional moieties into the framework of MSNs. The applications of mesoporous silica nanoprobes in magnetic resonance imaging, ultrasound imaging, computed tomography imaging, fluorescence imaging, positron emission computed tomography, photoacoustic (PA) imaging, and even multimodality imaging are discussed in detail. The biosafety of MSN‐based composite nanoplatforms as bioimaging nanoprobes is also highlighted, accompanied by a deep discussion on facing the challenges and future developments for guaranteeing their further potential clinical translation.