Search results for "ADSORPTION"

Characterization of the porous structure of Chilean volcanic soils by nitrogen adsorption and mercury porosimetry

2004

Pore volume, specific surface area (SSA), and total intragranular porosity (TIP) of Chilean soils derived from volcanic materials were studied. Soil samples involving the 0-15 and 15-30 cm depth of virgin and cultivated Collipulli (Ultisol) and Diguillin (Andisol) soils at two particle size fractions (<1 mm and <2 µm) were considered. From mercury porosimetry and N2 adsorption, mainly mesopores (pore diameter, dpore, about 10 nm) were determined for <1 mm Collipulli samples. Diguillin <1 mm soil shows macroporosity with dpore from 70 nm to 7000 nm. The clay fraction of Collipulli has macropores (dpore from 2000 nm to 40000 nm) and mesopores (dpore from 3 nm to 23 nm), while for Diguillin cl…

Water Structure in Proteins in Solid State Studied by Near Infrared Spectroscopy

2017

Water adsorption in proteins is the crucial process of protein folding and structure stabilizing. Adsorption of water on proteins can be evaluated by near-infrared spectroscopy, a useful technique for observing combination frequency of a water molecule. In this work, albumin, lysozyme, and silk, were used as models for α-helix and β-pleated sheet proteins. Their NIR spectra during water adsorption process were measured by using an NIR spectrometer equipped with a transflectance accessory. Moreover, the quantitative adsorption of water was determined by gravimetric technique. The results indicate that, there are five different NIR absorptions arise from the OH combination frequencies of wate…

The application protocol impacts the effectiveness of biocides against lichens

2020

Abstract This work analyzed the influence of different application protocols on the efficacy of two biocides against the foliose lichen Xanthoparmelia tinctina on the sandstones of the Roman Archaeological site of Luni (Italy). The hypotheses that (a) biocide application tools (brush vs. poultice), (b) pre-treatment hydration, and (c) post-treatment washing may affect devitalization success were verified by monitoring chlorophyll a fluorescence of thalli, both in situ and in laboratory conditions. The hypothesis that (d) stone substrate may act as reservoir for later biocide release under repeated cycles of wetting and drying was also assayed. Analyses confirmed the importance of the applic…

Optimal doses of caspofungin during continuous venovenous hemodiafiltration in critically ill patients

2017

Direct observation of alpha-lactalbumin, adsorption and incorporation into lipid membrane and formation of lipid/protein hybrid structures

2019

The interaction between proteins and membranes is of great interest in biomedical and biotechnological research for its implication in many functional and dysfunctional processes. We present an experimental study on the interaction between model membranes and alpha-lactalbumin (alpha-La). alpha-La is widely studied for both its biological function and its anti-tumoral properties. We use advanced fluorescence microscopy and spectroscopy techniques to characterize alpha-La-membrane mechanisms of interaction and alpha-La-induced modifications of membranes when insertion of partially disordered regions of protein chains in the lipid bilayer is favored. Moreover, using fluorescence lifetime imag…

Toxicity reduction of ochratoxin A by lactic acid bacteria.

2017

Abstract Ochratoxin A (OTA) is a mycotoxin produced by the metabolism of fungus belonging to the genus Aspergillus and Penicillium. In this paper we report, the capacity of different cultures of lactic acid bacteria (LAB) to degrade OTA present in MRS broth at both pH 3.5 and 6.5. A study of OTA reduction during gastrointestinal digestion carried out with the LAB was also performed. Taking into account the two reduction mechanisms of OTA studied in this work as the enzymatic one and the adsorption on the cell wall, as well as at pH 3.5 and 6.5 the reduction values of OTA were in a range of 30–99%, being the strains with greater reduction (97% and 95%) Lb. rhamnosus CECT 278T and Lb. plantar…

Protein denaturation caused by heat inactivation detrimentally affects biomolecular corona formation and cellular uptake

2018

Adsorption of blood proteins to the surface of nanocarriers is known to be the critical factor influencing cellular interactions and eventually determining the successful application of nanocarriers as drug carriers in vivo. There is an increasing number of reports summarizing large data sets of all identified corona proteins. However, to date our knowledge about the multiple mechanisms mediating interactions between proteins and nanocarriers is still limited. In this study, we investigate the influence of protein structure on the adsorption process and focus on the effect of heat inactivation of serum and plasma, which is a common cell culture procedure used to inactivate the complement sy…

Silica-gelatin hybrid sol-gel coatings: A proteomic study with biocompatibility implications.

2018

Osseointegration, including the foreign body reaction to biomaterials, is an immune‐modulated, multifactorial, and complex healing process in which various cells and mediators are involved. The buildup of the osseointegration process is immunological and inflammation‐driven, often triggered by the adsorption of proteins on the surfaces of the biomaterials and complement activation. New strategies for improving osseointegration use coatings as vehicles for osteogenic biomolecules delivery from implants. Natural polymers, such as gelatin, can mimic Collagen I and enhance the biocompatibility of a material. In this experimental study, two different base sol–gel formulations and their combinati…

2020

Worldwide, tons of lignin is produced annually in pulping plants and it is mainly considered as a waste material. Usually lignin is burned to produce energy for the pulping reactors. The production of value-added materials from renewable materials like lignin, has proved to be challenging. In this study, the effects of addition of three different types of lignin in the production of tannin/furanic foams is investigated. The foams were matured, first at 373 K and finally carbonized at 1073 K and the properties of them including mechanical strength, specific surface area and pore development are investigated before and after thermal treatment. According to the results, higher mechanical stren…

Immunoadsorption for treatment of severe atopic dermatitis.

2017

Atopic dermatitis (AD) is a common disease affecting up to 10-20% of the population with the largest disease burden in childhood. Treatment options include basic emollient treatment, topical as well as systemic immunosuppressants. The pathogenesis is complex and among various triggers, genetic predisposition and immunological alterations contribute to development of disease. Atopy is common in patients with AD and many patients have high levels of Immunoglobulin E (IgE), some of which recognizes exogenous or auto/self-allergens. Treatment options targeting IgE such as specific immunotherapy against e.g. house dust mites or using anti-IgE antibodies (omalizumab) showed variable results that …