Synthesis and compatibility evaluation of versatile mesoporous silica nanoparticles with red blood cells: an overview

Abstract

Protean mesoporous silica nanoparticles (MSNs) are propitious candidates over decades for nanoscale drug delivery systems due to their unique characteristics, including (but not limited to) changeable pore size, mesoporosity, high drug loading capacity, and biodegradability. MSNs have been drawing considerable attention as competent, safer and effective drug delivery vehicles day by day by their towering mechanical, chemical and thermal characteristics. Straightforward and easy steps are involved in the synthesis of MSNs at a relatively cheaper cost. This review reports Stober's synthesis, the first proposed synthesis procedure to prepare micron-sized, spherical MSNs, followed by other modifications later on done by scientists. To ensure the safety and compatibility of MSNs with biological systems, the hemocompatibility evaluation of MSNs using human red blood cells (RBCs) is a widely welcomed exercise. Though our main vision of this overview is to emphasize more on the hemocompatibility of MSNs to RBCs, we also brief about the synthesis and widespread applications of multifaceted MSNs. The strike of different parameters of MSNs plays a crucial role concerning the hemolytic activity of MSNs, which also has been discussed here. The inference is derived by centering some feasible measures that can be adopted to cut down or stop the hemolytic activity of MSNs in the future.

Fig. 1. TEM image of MCM-41 and SBA-15. Reprinted with permission from ref. 12. Copyright © 2008, American Chemical Society.

Fig. 2. Proposed LCT (liquid crystal templating) synthetic mechanism to form MCM-41 (ref. 21 and 22). Two pathways are involved during the synthesis process, as described earlier. Reprinted from ref. 22. Copyright © 1992 American Chemical Society.

Fig. 3. Different applications of MSNs. Represented with permission from ref. 10. Copyright © 2012 American Chemical Society.

Fig. 4. Hemolysis of RBC after interaction with bare MSNs.

Fig. 5. (a) Deformability Index (DI) of RBCs incubated with s-MSN (blue), AP1.5-s-MSN (green), PEG1-s-MSN (black), CA1.5-s-MSN (purple), and l-MSN (red). (b) Flow cytometry analyses of RBCs incubated with FITC-l-MSN (red), FITC-s-MSN (blue), AP1.5-FITC-s-MSN (green), PEG1-FITC-s-MSN (black), and CA1.5-FITC-s-MSN (purple). Reproduced with permission from ref. 6. Copyright © 2011 American Chemical Society.

Fig. 6. Effect of Protein-corona (P.C.) on the hemolytic activity of MSNs. This schematic shows that P.C. is formed on the surface of MSNs in the presence of Blood Plasma (B.P.) [B.P.: positive] and not formed in the absence of blood plasma [B.P.: negative]. This P.C. formation further prevents the interaction of MSNs with RBCs and thus reduces the hemolysis.

Fig. 7. Diagrammatic representation of MSN hemocompatibility with RBCs.