Fullerenol-Capped Porous Silica Nanoparticles for pH-Responsive Drug Delivery (original) (raw)
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The Engineering of Porous Silica and Hollow Silica Nanoparticles to Enhance Drug-loading Capacity
Processes, 2019
As a promising candidate for expanding the capacity of drug loading in silica nanoplatforms, hollow mesoporous silica nanoparticles (HMSNs) are gaining increasing attention. In this study, porous nanosilica (PNS) and HMSNs were prepared by the sol-gel method and template assisted method, then further used for Rhodamine (RhB) loading. To characterize the as-synthesized nanocarriers, a number of techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen absorption-desorption isotherms, dynamic light scattering (DLS), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR) were employed. The size of HMSN nanoparticles in aqueous solution averaged 134.0 ± 0.3 nm, which could be adjusted by minor changes during synthesis, whereas that of PNS nanoparticles was 63.4 ± 0.6 nm. In addition, the encapsulation of RhB into HMSN nanoparticles to form RhB-loaded nanocarriers (RhB/HMSN) was successful, achieving high loading efficie...
Designed Monomers and Polymers, 2013
The aim of this study is the synthesis of pH-responsive cationic silica nanoparticles (NPs) by pyridinium-based ionic liquid for the improved sustained release formulations of methotrexate (MTX) as an anionic anticancer drug. Fanctionalized cationic silica NPs were successfully prepared via graft copolymerization of methacrylic acid (MAA) onto vinyl-bond-modified silica NPs. The prepared NPs were characterized using the scanning electron microscopy (SEM), the infrared spectroscopy (IR), and the thermogravimetric analysis. The resultant NPs were uniform spherical NPs with a mean diameter of approximately 160 ± 20 nm. We explored the ionic interaction of MTX NPs in order to generate pH-responsive controlled release system. The cumulative release of MTX-loaded composite microspheres shows a highly desirable precise pH-responsive drug release performance, i.e. loaded drug would not leak in physiological pH (7.4), but would release in a sustained way, where the pH value is lower (4). The protonation of carboxyl groups at mildly acidic condition resulted in a faster dissociation of copolymer/MTX complex, leading to an accelerated release of MTX at pH 4. Thus, complexation of MTX with NPs yielded a drug delivery system affording a pH-triggered release of MTX in an acidic environment. The in vitro cytotoxicity test by MTT assay against breast cancer cells, MCF7 indicates that NPs are nontoxic and suitable to use as drug carriers. Antitumor activity of the MTX-loaded nanocomposites against the cells was kept over the whole experiment process. The results showed that the MTX could be released from the nanocomposites without losing cytotoxicity.
Targeting of Porous Hybrid Silica Nanoparticles to Cancer Cells
ACS Nano, 2009
Mesoporous silica nanoparticles functionalized by surface hyperbranching polymerization of poly(ethylene imine), PEI, were further modified by introducing both fluorescent and targeting moieties, with the aim of specifically targeting cancer cells. Owing to the high abundance of folate receptors in many cancer cells as compared to normal cells, folic acid was used as the targeting ligand. The internalization of the particles in cell lines expressing different levels of folate receptors was studied. Flow cytometry was used to quantify the mean number of nanoparticles internalized per cell. Five times more particles were internalized by cancer cells expressing
Journal of Biomaterials Science, Polymer Edition, 2020
The synthesis of drug delivery systems based on hollow mesoporous silica nanoparticles (MSNs) is still a major challenge. In this work, the hollow hybrid MSNs were successfully prepared by cetyltrimethylammonium bromide-directed sol−gel process and one-step hydrothermal treatment process. The hollow hybrid MSNs had hybrid ethane bridged frameworks with the uniform particle size (250 nm) and mesoporous pore diameter (3.7 nm). The polyacrylic acid (PAA) encapsulated drug delivery system based on hollow hybrid MSNs was prepared by using silanization, surface modification, doxorubicin hydrochloride (DOX) loading, and PAA coating. Drug encapsulation and release behavior at different temperatures and pH were studied by using DOX as a model guest molecule. The results displayed that the modified hollow ethane bridged MSNs possessed good biocompatibility and excellent thermal/pH-dual sensitive drug release property. This novel thermal/pH-sensitive drug delivery system based on hollow ethane bridged MSNs has the advantages of feasible synthesis, no cytotoxicity, and good drug loading capacity, which may have potential applications in the anti-cancer therapy.
bioengineering pH-Responsive Mesoporous Silica and Carbon Nanoparticles for Drug Delivery
Bioengineering , 2017
The application of nanotechnology to medicine constitutes a major field of research nowadays. In particular, the use of mesoporous silica and carbon nanoparticles has attracted the attention of numerous researchers due to their unique properties, especially when applied to cancer treatment. Many strategies based on stimuli-responsive nanocarriers have been developed to control the drug release and avoid premature release. Here, we focus on the use of the subtle changes of pH between healthy and diseased areas along the body to trigger the release of the cargo. In this review, different approximations of pH-responsive systems are considered: those based on the use of the host-guest interactions between the nanocarriers and the drugs, those based on the hydrolysis of acid-labile bonds and those based on supramolecular structures acting as pore capping agents.
Chemistry - A European Journal, 2014
Mesoporous silica nanoparticles (MSNPs) are functionalized with molecular-recognition sites by anchoring a triazine or uracil fragment on the surface. After loading these MSNPs with dyes (propidium iodide or rhodamine B) or with a drug (camptothecin, CPT) they are capped by the complementary fragments, uracil and adenine, respectively, linked to the bulky cyclodextrin ring. These MSNPs are pH-sensitive and indeed, the dye release was observed at acidic pH by continuously monitored fluorescence spectroscopy studies. On the other hand, no dye leakage occurred at neutral pH, hence meeting the non-premature requirement to minimize side effects. In vitro studies were performed and confocal microscopy images demonstrate the internalization of the MSNPs and also dye release in the cells. To investigate the drug-delivery performance, the cytotoxicity of CPT-loaded nanoparticles was tested and cell death was observed. A remarkably lower amount of loaded CPT in the MSNPs (more than 40 times less) proved to be as efficient as free CPT. These results not only demonstrate the drug release after pore opening under lysosomal pH, but they also show the potential use of these MSNPs to significantly decrease the amount of the administered drug.
pH-Dependent silica nanoparticle dissolution and cargo release
Colloids and surfaces. B, Biointerfaces, 2018
The dissolution of microporous silica nanoparticles (NP) in aqueous environments of different biologically relevant pH was studied in order to assess their potential as drug delivery vehicles. Silica NPs, loaded with fluorescein, were prepared using different organosilane precursors (tetraethoxysilane, ethyl triethoxysilane or a 1:1 molar ratio of both) and NP dissolution was evaluated in aqueous conditions at pH 4, pH 6 and pH 7.4. These conditions correspond to the acidity of the intracellular environment (late endosome, early endosome, cytosol respectively) and gastrointestinal tract ('fed' stomach, duodenum and jejunum respectively). All NPs degraded at pH 6 and pH 7.4, while no dissolution was observed at pH 4. NP dissolution could be clearly visualised as mesoporous hollows and surface defects using electron microscopy, and was supported by UV-vis, fluorimetry and DLS data. The dissolution profiles of the NPs are particularly suited to the requirements of oral drug del...
Acta Chimica Slovenica, 2020
Inorganic structures with functionalized polymers play essential roles in diverse biological trends. Herein, thermal and CO 2 dual-stimuli nanomaterials composed of mesoporous silica nanoparticles (MSN) anchored with two grafted copolymers: poly(3-methacryloxypropyltrimethoxysilane) "PMPS" & poly(N,N-dimethylaminoethyl methacrylate) "PDMAE-MA" were synthesized via one-step reaction and characterized by BET as well as BJH methods to estimate pore sizes, pore volumes, and surface areas. The smart PDMAEMA acted as an active gatekeeper to adjust the loading or in vitro release processes of a fungicidal drug-loaded inside the mesopores by altering temperature or CO 2 of the tested environment. Furthermore, treating the nanomaterials by CO 2 for a few minutes was found to have a bactericidal effect with promising results as indicated by the disk diffusion technique. In general, the positive biological activity against selected strains of bacteria and fungi indicates that these particles may be helpful for engineering more efficient antifungal or antibacterial agents for pharmaceutical applications.
Fe3O4–silica core–shell nanoporous particles for high-capacity pH-triggered drug delivery
Journal of Materials Chemistry, 2012
We demonstrate a one-step procedure for the synthesis of Fe 3 O 4 -silica core-shell nanoparticles with hierarchically ultra-large pores independent of any post-treatment such as annealing and templatemolecule removal. The nanoporous silica shells with available amine groups were functionalized by clickable linkers to produce pH-sensitive amides for regulating the release of an anti-cancer drug, doxorubicin (DOX). The loading amount of DOX reached up to 13.2 mg per 100 mg nanoparticles, 74.2% of which can be effectively released after 63 h at body temperature and pH 5 with decreased side effects. Such excellent features of these nanoparticles appear to arise from the integrated hierarchically ultra-large open-porosities and a homogeneous dispersibility in aqueous solution that has a great potential for their use as drug delivery systems.