Mesoporous silica nanoparticles: synthesis, classification, drug loading, pharmacokinetics, biocompatibility, and application in drug delivery

ABSTRACT

Introduction: Mesoporous silica nanoparticles (MSNs) feature a high surface area and large pore volume, uniform and tunable pore size, and stable framework; thus, they have been used extensively as drug carriers.

Areas covered: The synthesis, classification, and the latest generation of MSNs, drug loading methods, modification of MSNs, pharmacokinetic studies, biocompatibility, and toxicity of MSNs, and their application in drug delivery systems (DDS) are covered in this review.

Expert opinion: It is crucial to uncover the mechanism for the formation of MSNs. Before drug loading, the characteristics of MSNs should be taken into consideration. In addition, the porosity, particle size and morphology, surface oxidation and surface functionalization can also influence the in vivo fate of MSNs, which is worthy of further study. Coating MSNs with novel materials may improve their biocompatibility, control the release of drugs loaded into the MSNs or enhance the uptake of the coated MSNs by tumor cells. MSNs can also be used as carriers for combination therapy in the treatment of cancer. Despite the rapid development of MSNs, the biological effects of these biomaterials remain relatively less understood.

KEYWORDS:

• Mesoporous silica nanoparticles
• drug loading
• pharmacokinetic study
• biocompatibility and toxicity
• controlled/targeted drug delivery

Article highlights

• For the synthesis of MSNs, we have explored the synthesis of MSNs in depth and discussed the parameters affecting the MSNs characteristic.

• Traditional MSNs, like MCM systems, SBA systems and KIT systems, and new generation of MSNs, like hollow MSNs, lipid bilayer-coated MSNs, and other modified MSNs are introduced in this review.

• The absorption, distribution, and excretion of MSNs by intravenous or oral administration, which are the main routes for possible biomedical application of MSNs are shown.

• From the genotoxicity to the tissue biocompatibility, MSNs show no significant toxicity.

• As drug carriers, MSNs have been used to improve the solubility of insoluble drugs, for controlled/targeted delivery of drugs or for theranostics.

• In the future, coating MSNs with more novel materials (such as titania, lipid bilayer, RBC membrane or even tumor cell membrane) may improve their biocompatibility, control the release of drugs loaded into the MSNs or enhance the uptake of the coated MSNs by tumor cells.

This box summarizes key points contained in the article.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.