Deformable Hollow Periodic Mesoporous Organosilica Nanocapsules for Significantly Improved Cellular Uptake

Abstract

Mesoporous solids have been widely used in various biomedical areas such as drug delivery and tumor therapy. Although deformability has been recognized as a prime important characteristic influencing cellular uptake, the synthesis of deformable mesoporous solids is still a great challenge. Herein, deformable thioether-, benzene-, and ethane-bridged hollow periodic mesoporous organosilica (HPMO) nanocapsules have successfully been synthesized for the first time by a preferential etching approach. The prepared HPMO nanocapsules possess uniform diameters (240-310 nm), high surface areas (up to 878 m·g), well-defined mesopores (2.6-3.2 nm), and large pore volumes (0.33-0.75 m·g). Most importantly, the HPMO nanocapsules simultaneously have large hollow cavities (164-270 nm), thin shell thicknesses (20-38 nm), and abundant organic moiety in the shells, which endow a lower Young's modulus (E) of 3.95 MPa than that of solid PMO nanoparticles (251 MPa). The HPMOs with low E are intrinsically flexible and deformable in the solution, which has been well-characterized by liquid cell electron microscopy. More interestingly, it is found that the deformable HPMOs can easily enter into human breast cancer MCF-7 cells via a spherical-to-oval morphology change, resulting in a 26-fold enhancement in cellular uptake (43.1% cells internalized with nanocapsules versus 1.65% cells with solid counterparts). The deformable HPMO nanocapsules were further loaded with anticancer drug doxorubicin (DOX), which shows high killing effects for MCF-7 cells, demonstrating the promise for biomedical applications.

Virus‐Inspired Deformable Mesoporous Nanocomposites for High Efficiency Drug Delivery

“…The rational design of organic–inorganic hybrid mesoporous framework may be useful to overcome this limitation. Lu and Zhao et al suggested that several factors should be fulfilled to fabricate deformable mesoporous silica, such as high content of noncross‐linked free groups, and hollow structure with ultrathin shell . Based on these principles, they successfully fabricated deformable hollow periodic mesoporous organosilica nanocapsules via an organosilane‐assisted selective etching strategy.…”

“…The inhomogeneous stress distribution of the outer shell resulted in cross‐wrinkled structure. After 1 h (denoted as YEMO‐60), the thickness of the outer shell of YEMO reached up to ≈15 nm, and the cross‐wrinkled capsules shell transform to a smoother shell with relatively rigid framework, which is similar to a reinforced process of mesoporous framework (Figure S2, Supporting Information) . The size of YEMO nanocomposites was also measured via dynamic light scattering as shown in Figure S3 (Supporting Information).…”

Interfacial Assembly of Mesoporous Silica‐Based Optical Heterostructures for Sensing Applications

“…Zhao's group reported a series of flexible thioether‐, benzene‐, and ethane‐bridged hollow PMO (HPMO) nanocapsules by a preferential etching approach ( Figure a). Moreover, these HPMO nanocapsules possess large hollow cavities, thin shell thicknesses, and diverse functional groups in the mesoporous shells …”

“…a) i) Illustration of the formation mechanism of the deformable HPMO nanocapsules, ii–iv) TEM images of ii) thioether‐bridged, iii) benzene‐bridged, and iv) ethane‐bridged HPMO nanocapsules prepared by etching the corresponding organosilica nanospheres in a mild NaOH solution. a) Reproduced with permission . Copyright 2017, American Chemical Society.…”

Robust Synthesis of Gold‐Based Multishell Structures as Plasmonic Catalysts for Selective Hydrogenation of 4‐Nitrostyrene

“…As ar esult, the inward diffusion of BH 4 À is much faster than outward diffusion of Au species.T hese diffusion rate distinctions finally lead to formation of multishell structures. [22][23][24] UV/Vis-NIR spectra (Figure 3d)ofthree samples (S-PSSAu, S-PDSAu, and S-PTSAu) with same Au concentration were determined to investigate their light absorption property. Accompanied by the increasing shell number, increased lightharvesting is observed, which may be caused by the presence of additional incident light reflections in the structures with more shells.…”