| 1. |
- Afonso, Damien, et al.
(författare)
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Multivalent mesoporous silica nanoparticles photo-delivering nitric oxide with carbon dots as fluorescence reporters
- 2017
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Ingår i: Nanoscale. - : ROYAL SOC CHEMISTRY. - 2040-3364 .- 2040-3372. ; 9:36, s. 13404-13408
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Tidskriftsartikel (refereegranskat)abstract
- Amino-terminated mesoporous silica nanoparticles embedding carbon dots (MSCD) formed by calcination were functionalized with a nitric oxide (NO) photodonor (1) to give a robust MSCD-1 conjugate. The intense fluorescence of MSCDs was strongly quenched in MSCD-1 by effective energy transfer. Visible light excitation of MSCD-1 liberates NO, suppresses the energy transfer mechanism and leads to concomitant fluorescence restoration of the MSCD scaffold, which acts as an optical reporter for the released NO. The MSCD-1 hybrid is also able to encapsulate the highly hydrophobic photosensitizer temoporfin, preserving the fluorescence reporting function.
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| 2. |
- Afonso, Damien, et al.
(författare)
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Multivalent mesoporous silica nanoparticles photodelivering nitric oxide with carbon dots as fluorescent reporters
- 2017
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Ingår i: Nanoscale. - : Royal Society of Chemistry. - 2040-3364 .- 2040-3372. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Amino-terminated mesoporous silica nanoparticles embedding carbon dots (MSCD) formed by calcination were functionalized with a nitric oxide (NO) photodonor (1) to give a robust MSCD-1 conjugate. The intense fluorescence of MSCDs was strongly quenched in MSCD-1 by effective energy transfer. Visible light excitation of MSCD-1 liberates NO, suppresses the energy transfer mechanism and leads to concomitant fluorescence restoration of the MSCD scaffold, which acts as an optical reporter for the released NO. The MSCD-1 hybrid is also able to encapsulate the highly hydrophobic photosensitizer temoporfin, preserving the fluorescence reporting function.
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| 3. |
- Angiolini, Lorenzo, et al.
(författare)
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Fluorescence imaging of antibiotic clofazimine encapsulated within mesoporous silica particle carriers : relevance to drug delivery and the effect on its release kinetics
- 2018
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Ingår i: Physical Chemistry, Chemical Physics - PCCP. - : Royal Society of Chemistry. - 1463-9076 .- 1463-9084. ; 20:17, s. 11899-11911
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Tidskriftsartikel (refereegranskat)abstract
- We report on the encapsulation of the antibiotic clofazimine (CLZ) within the pores of mesoporous silica particles having hydrophilic (CBET value of 137) and more hydrophobic (CBET value of 94 after calcination at 600 °C) surfaces. We studied the effect of pH on the released amount of CLZ in aqueous solutions and observed a maximum at pH 4.1 in correlation with the solubility of the drug. Less release of the drug was observed from the more hydrophobic particles which was attributed to a difference in the affinity of the drug to the carrier particles. Fluorescence lifetime imaging microscopy, emission spectra, and fluorescence lifetimes of single drug loaded particles provided detailed understanding and new knowledge of the physical form of the encapsulated drug and the distribution within the particles. The distribution of CLZ within the particles was independent of the surface chemistry of the particles. The confirmation of CLZ molecules as monomers or aggregates was revealed by controlled removal of the drug with solvent. Additionally, the observed optical "halo effect" in the fluorescent images was interpreted in terms of specific quenching of high concentration of molecules. The emission lifetime experiments suggest stronger interaction of CLZ with the more hydrophobic particles, which is relevant to its release. The results reported in this work demonstrate that tuning the hydrophilicity/hydrophobicity of mesoporous silica particles can be used as a tool to control the release without impacting their loading ability.
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| 4. |
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| 5. |
- Campos Pacheco, Jesús Enrique, et al.
(författare)
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Inhalable porous particles as dual micro-nano carriers demonstrating efficient lung drug delivery for treatment of tuberculosis
- 2024
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Ingår i: Journal of Controlled Release. - : Elsevier B.V.. - 0168-3659 .- 1873-4995. ; 369, s. 231-250
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Tidskriftsartikel (refereegranskat)abstract
- Inhalation therapy treating severe infectious disease is among the more complex and emerging topics in controlled drug release. Micron-sized carriers are needed to deposit drugs into the lower airways, while nano-sized carriers are of preference for cell targeting. Here, we present a novel and versatile strategy using micron-sized spherical particles with an excellent aerodynamic profile that dissolve in the lung fluid to ultimately generate nanoparticles enabling to enhance both extra- and intra-cellular drug delivery (i.e., dual micro-nano inhalation strategy). The spherical particles are synthesised through the condensation of nano-sized amorphous silicon dioxide resulting in high surface area, disordered mesoporous silica particles (MSPs) with monodispersed size of 2.43 μm. Clofazimine (CLZ), a drug shown to be effective against multidrug-resistant tuberculosis, was encapsulated in the MSPs obtaining a dry powder formulation with high respirable fraction (F.P.F. <5 μm of 50%) without the need of additional excipients. DSC, XRPD, and Nitrogen adsorption-desorption indicate that the drug was fully amorphous when confined in the nano-sized pores (9–10 nm) of the MSPs (shelf-life of 20 months at 4 °C). Once deposited in the lung, the CLZ-MSPs exhibited a dual action. Firstly, the nanoconfinement within the MSPs enabled a drastic dissolution enhancement of CLZ in simulated lung fluid (i.e., 16-fold higher than the free drug), increasing mycobacterial killing than CLZ alone (p = 0.0262) and reaching concentrations above the minimum bactericidal concentration (MBC) against biofilms of M. tuberculosis (i.e., targeting extracellular bacteria). The released CLZ permeated but was highly retained in a Calu-3 respiratory epithelium model, suggesting a high local drug concentration within the lung tissue minimizing risk for systemic side effects. Secondly, the micron-sized drug carriers spontaneously dissolve in simulated lung fluid into nano-sized drug carriers (shown by Nano-FTIR), delivering high CLZ cargo inside macrophages and drastically decreasing the mycobacterial burden inside macrophages (i.e., targeting intracellular bacteria). Safety studies showed neither measurable toxicity on macrophages nor Calu-3 cells, nor impaired epithelial integrity. The dissolved MSPs also did not show haemolytic effect on human erythrocytes. In a nutshell, this study presents a low-cost, stable and non-invasive dried powder formulation based on a dual micro-nano carrier to efficiently deliver drug to the lungs overcoming technological and practical challenges for global healthcare.
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| 6. |
- Corkery, Robert W., 1967-, et al.
(författare)
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Anti-caking agent for flavored products
- 2010
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Patent (populärvet., debatt m.m.)abstract
- The present invention generally relates to the use of porous particles to control the release of a liquid, such as the release of a flavor in a food product. Liquid components, such as flavorants, are loaded into porous particles to form a composition. The pore diameter, pore tortuosity and loading parameters determine the characteristics of the composition and the release profile of the liquid.
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| 7. |
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| 8. |
- Feiler, Adam A., et al.
(författare)
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Adsorption and viscoelastic properties of fractionated mucin (BSM) and bovine serum albumin (BSA) studied with quartz crystal microbalance (QCM-D)
- 2007
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Ingår i: Journal of Colloid and Interface Science. - : Elsevier BV. - 0021-9797 .- 1095-7103. ; 315:2, s. 475-481
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Tidskriftsartikel (refereegranskat)abstract
- The adsorption profile and viscoelastic properties of bovine submaxillary gland mucin (BSM) and bovine serum albumin (BSA), extracted from a commercial mucin preparation, adsorbing to polystyrene surfaces has been studied using quartz crystal microbalance with dissipation monitoring (QCM-D). A significant difference in the adsorption properties of the different proteins was detected; with the BSA adsorbing in a flat rigid layer whilst the mucin adsorbed in a diffuse, highly viscoelastic layer. Subsequent addition of BSA to the preadsorbed mucin layer resulted in stiffening of the protein layer which was attributed to complexation of the mucin by BSA. In contrast, a preadsorbed layer of BSA prevented mucin adsorption altogether. Combined mixtures of mucin and BSA in well defined ratios revealed intermediate properties between the two separate protein species which varied systematically with the protein ratios. The results shed light on the synergistic effects of complexation of lower molecular weight biomolecular species with mucin. The possibility to selectively control protein uptake and tailor the physical properties of the adsorbed layer makes mucin an attractive option for application in biomaterial coatings.
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| 9. |
- Feiler, Adam A., et al.
(författare)
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Adsorption of anionic gold nanoparticles by a layer of cationic microgel particles deposited on a gold-coated, quartz surface : studied by quartz crystal microbalance and atomic force microscopy
- 2011
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Ingår i: Soft Matter. - : Royal Society of Chemistry (RSC). - 1744-683X .- 1744-6848. ; 7:14, s. 6660-6670
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Tidskriftsartikel (refereegranskat)abstract
- The uptake of gold [Au-MES] nanoparticles by pH-responsive poly(2-vinylpyridine) [P2VP] microgel particles, deposited on a surface, has been studied using a quartz crystal microbalance with dissipation monitoring [QCM-D]. QCM-D, which has not previously been applied to such systems, has been shown to be a promising technique for their analysis, especially when combined with a complementary technique such as atomic force microscopy [AFM]. The QCM-D technique, which provides information on mass and viscosity changes of material adsorbed to a surface, has been used to follow the adsorption of microgel particles to a surface, their subsequent swelling and collapse due to changing the system pH, and the uptake of Au-MES nanoparticles by the P2VP particles. Microgel particles with differing cross-linker content have been compared, following uptake by microgel particles in both their collapsed and swollen states. Qualitative differences in the QCM-D response were observed between microgels with differing cross-linker content (and hence different swelling properties). It was shown that uptake of Au-MES nanoparticles acted to fully and irreversibly collapse the swollen P2VP microgels, inhibiting their pH response. The Sauerbrey relationship was used to equate frequency changes measured by QCM-D to mass allowing sorption amounts for the uptake of Au-MES nanoparticles by P2VP particles to be obtained for these surface-constrained systems.
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| 10. |
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