Layer by layer growth of silver chloride nanoparticle within the pore channels of SBA-15/SO3H mesoporous silica (AgClNP/SBA-15/SO3K): Synthesis, characterization and antibacterial properties

AbstractWe studied adsorption, growth and desorption of Xe on Nb(110) using an in-situ obliqueincidence reflectivity difference (OI-RD) technique and low energy electron diffraction (LEED) from 32 K to 100 K. The results show that Xe grows a (111)-oriented film after a transition layer is formed on Nb(110). The transition layer consists of three layers. The first two layers are disordered with Xe-Xe separation significantly larger than the bulk value. The third monolayer forms a close packed (111) structure on top of the tensile-strained double layer and serves as a template for subsequent homoepitaxy. The adsorption of the first and the second layers are zeroth order with sticking coefficient close to one. Growth of the Xe(111) film on the transition layer proceeds in a step flow mode from 54K to 40K. At 40K, an incomplete layer-by-layer growth is observed while below 35K the growth proceeds in a multilayer mode.

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Layer-by-layer assembly of hyaluronic acid/carboxymethylchitosan polyelectrolytes on the surface of aminated mesoporous silica for the oral delivery of 5-fluorouracil

European Polymer Journal ◽

10.1016/j.eurpolymj.2017.06.033 ◽

2017 ◽

Vol 93 ◽

pp. 572-589 ◽

Cited By ~ 31

Author(s):

Thayyath S. Anirudhan ◽

Chithra S. Vasantha ◽

Athira V. Sasidharan

Keyword(s):

Hyaluronic Acid ◽

Mesoporous Silica ◽

Oral Delivery ◽

Layer By Layer ◽

Layer By Layer Assembly ◽

Layer Assembly

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Cylindrical Microparticles Composed of Mesoporous Silica Nanoparticles for the Targeted Delivery of a Small Molecule and a Macromolecular Drug to the Lungs: Exemplified with Curcumin and siRNA

Pharmaceutics ◽

10.3390/pharmaceutics13060844 ◽

2021 ◽

Vol 13 (6) ◽

pp. 844

Author(s):

Thorben Fischer ◽

Inga Winter ◽

Robert Drumm ◽

Marc Schneider

Keyword(s):

Mesoporous Silica ◽

Silica Nanoparticles ◽

Targeted Delivery ◽

Mesoporous Silica Nanoparticles ◽

Alveolar Epithelial Cells ◽

In Vitro Toxicity ◽

Layer By Layer ◽

Necrosis Factor Alpha ◽

Aerodynamic Properties ◽

Tnf Α

The transport of macromolecular drugs such as oligonucleotides into the lungs has become increasingly relevant in recent years due to their high potency. However, the chemical structure of this group of drugs poses a hurdle to their delivery, caused by the negative charge, membrane impermeability and instability. For example, siRNA to reduce tumour necrosis factor alpha (TNF-α) secretion to reduce inflammatory signals has been successfully delivered by inhalation. In order to increase the effect of the treatment, a co-transport of another anti-inflammatory ingredient was applied. Combining curcumin-loaded mesoporous silica nanoparticles in nanostructured cylindrical microparticles stabilized by the layer-by-layer technique using polyanionic siRNA against TNF-α was used for demonstration. This system showed aerodynamic properties suited for lung deposition (mass median aerodynamic diameter of 2.85 ± 0.44 µm). Furthermore, these inhalable carriers showed no acute in vitro toxicity tested in both alveolar epithelial cells and macrophages up to 48 h incubation. Ultimately, TNF-α release was significantly reduced by the particles, showing an improved activity co-delivering both drugs using such a drug-delivery system for specific inhibition of TNF-α in the lungs.

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Modeling the Layer-by-Layer Growth of HKUST-1 Metal-Organic Framework Thin Films

Nanomaterials ◽

10.3390/nano11071631 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1631

Author(s):

Qiang Zhang ◽

Yohanes Pramudya ◽

Wolfgang Wenzel ◽

Christof Wöll

Keyword(s):

Thin Films ◽

Surface Roughness ◽

Deposition Rate ◽

Layer Growth ◽

Coarse Grained ◽

Structural Defects ◽

Effect Of Temperature ◽

Layer By Layer ◽

Reactant Concentration ◽

Metal Organic

Metal organic frameworks have emerged as an important new class of materials with many applications, such as sensing, gas separation, drug delivery. In many cases, their performance is limited by structural defects, including vacancies and domain boundaries. In the case of MOF thin films, surface roughness can also have a pronounced influence on MOF-based device properties. Presently, there is little systematic knowledge about optimal growth conditions with regard to optimal morphologies for specific applications. In this work, we simulate the layer-by-layer (LbL) growth of the HKUST-1 MOF as a function of temperature and reactant concentration using a coarse-grained model that permits detailed insights into the growth mechanism. This model helps to understand the morphological features of HKUST-1 grown under different conditions and can be used to predict and optimize the temperature for the purpose of controlling the crystal quality and yield. It was found that reactant concentration affects the mass deposition rate, while its effect on the crystallinity of the generated HKUST-1 film is less pronounced. In addition, the effect of temperature on the surface roughness of the film can be divided into three regimes. Temperatures in the range from 10 to 129 °C allow better control of surface roughness and film thickness, while film growth in the range of 129 to 182 °C is characterized by a lower mass deposition rate per cycle and rougher surfaces. Finally, for T larger than 182 °C, the film grows slower, but in a smooth fashion. Furthermore, the potential effect of temperature on the crystallinity of LbL-grown HKUST-1 was quantified. To obtain high crystallinity, the operating temperature should preferably not exceed 57 °C, with an optimum around 28 °C, which agrees with experimental observations.

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