Toxin removal adsorption

A comparison of the extent of toxin removal under dark and light conditions for cases of high and low dark adsorption of toxin to the semiconductor surface is shown in Figure 9. For the high MLR adsorption case (58.1% and 21.7% MLR and AE adsorbed to Ti02 respectively), pseudo-first order removal of toxin from solution is observed with essentially all toxin degraded in the first 30 minutes. This result closely matches that observed by Feitz et al. Environ, ScL TechnoL submitted) at pH 3.5. In the low adsorption case (0% and 7.7% MLR... 

The removal of ochratoxin A and patulin from solution by 30 different LAB was studied by Fuchs et al. (2008). Results showed thatL. acidophilus was able to remove at least 95% of ochratoxin A from liquid medium, while Bifidobacterium animalis was able to bind and remove 80% of patulin in solution. Hatab, Yue, and Mohamad (2012) also studied the ability of LAB strains to remove patuhn from liquid medium, in this case apple juice. All 10 strains used in the experiments were able to remove the toxin, at significantly different amounts, with best binding ability shown by L rhamnosus 6224 (80.4%) and Enterococcus faecium 21605 (64.5%). According to the authors, the optimal mycotoxin removal was achieved at 30 °C, the binding was toxin concentration dependent (the amount of toxin removal increased with decreasing toxin levels) and the adsorption of patulin by LAB had no negative impact on the quality of the apple juice, based on various quahty parameters (Hatab et al., 2012). 

When investigating ranoval of deoxynivalenol from solution by LAB, Franco, Garcia, Hirooka, Ono, and dos Santos (2011) reported that both viable and nonviable cells (heat inactivated by pasteurization or sterilization) led to toxin removal. However, inactivated cells bound more deoxynivalenol from solution than viable cells, with all cells inactivated by sterilization showing a significant iuCTease in binding compared to viable cells. According to the authors, this indicates that the main mechanism of detoxification was adsorption of mycotoxin by the cell components of LAB. Since the heat treatment most likely exposed cell wall components and plasma manbranes that would not be available otherwise, an increase in adsorption by those treated cells would be expected, which was confirmed by the experiment results (Franco et al., 2011). 

Immunoadsorption is another way to remove middle molecules, either specifically or nonspecificaUy. Adsorptive processes can be carried out either by chemically modifying a hemodialysis membrane to create adsorption sites or by the use of an add-on device during hemodialysis. It should be mentioned that the 1 to 2-m membrane surface area on the hollow-fiber lumen is much smaller than the surface area within the porous membrane structure and may be insuBicient to provide significant toxin removal. However, one could argue that adsorptive sites within the membrane wall offer httle benefit unless significant back filtration of a toxin is taking place because it makes no difference to the patient whether a toxin is adsorbed within the membrane walls or flushed away with the spent dialysate. 

Adsorption for Toxin Removal Over the past several years, there have... 

Minimization of agricultural losses from soil toxins Toxins from soils appear to be responsible for inhibition of nitrogen fixation, metabolism and nodulation in legumes. Removal of toxins could be achieved by proper adsorption techniques and also by growing companion plants that contribute organic matter to microoranisms which help to destroy or degrade toxic chemicals. 

Contrary to carbon enterosorbents, Enterosgel does not possess an ability for selective removal of albumin-bound ligands regardless of their affinity with the protein carrier - weak (L-tryptophane), medium (sodium caprylate, deoxycholic acid), or strong (indole-3-carboxylic acid and unconjugated bilirubin). It means that if protein-bound toxins are removed by Enterosgel, this occurs simultaneously with adsorption of the carrier protein. 

Although certain simple functions of the liver, such as the removal of some toxins, can be performed by using dialysis and adsorption with activated charcoal, it is clear that such a simple artificial approach cannot perform the complex functions of the liver, and that any practical liver support system must use living hepatocytes. It should be mentioned at this point that hepatocytes have an anchorage-dependent nature that is, they require a form of anchor (i.e., a solid surface or scaffold) on which to grow. Thus, the use of single-cell suspensions is not appropriate for liver cell culture, and fiver cells attached to solid surfaces are normally used. Encapsulated fiver cells and spheroids (i.e., spherical aggregates of fiver cells) may also be used for this purpose. 

For this purpose, the removal procedures are mainly based on membrane separation that ideally should bring free and bound toxins to a nonspedfic adsorption device (ion-exchangers and/or activated charcoal). Blood should not perfuse directly such components, due to bioincompatibity aspeds. Therefore, several processes have been proposed to correctly handle toxins carried by plasma [27]. They are described in the following sections. All of them need a physical barrier between the blood cells and the adsorption system. This physical sieve is always a membrane with adequate properties, through which toxins can be transferred by diffusion or convection. 

Removal or elimination of mycotoxins. Since most of the mycotoxin burden in contaminated commodities is localized to a relatively small number or seeds or kernels [reviewed in Dickens, 200], removal of these contaminated seeds/kemels is effective in detoxifying the commodity. Methods currently used include (a) physical separation by identification and removal of damaged seeds, mechanical or electronic sorting, flotation and density separation of damaged or contaminated seeds (b) removal by filtration and adsorption onto filter pads, clays, activated charcoal (c) removal of the toxin by milling processes and (d) removal of the mycotoxin by solvent extraction. 

Adsorbents are used in medicine mainly for the treatment of acute poisoning, whereas other extracorporeal techniques based on physico-chemical principles, such as dialysis and ultrafiltration, currently have much wider clinical applications [1]. Nevertheless, there are medical conditions, such as acute inflammation, hepatic and multi-organ failure and sepsis, for which mortality rates have not improved in the last forty years. These conditions are usually associated with the presence of endotoxin - lipopolysaccharide (LPS) or inflammatory cytokines - molecules of peptide/protein nature [2]. Advantages of adsorption over other extracorporeal techniques include ability to adsorb high molecular mass (HMM) metabolites and toxins. Conventional adsorbents, however, have poor biocompatibility. They are used coated with a semipermeable membrane of a more biocompatible material to allow for a direct contact with blood. Respectively, ability of coated adsorbents to remove HMM solutes is dramatically reduced. In this paper, preliminary results on adsorption of LPS and one of the most common inflammatory cytokines, TNF-a, on uncoated porous polymers and activated carbons, are presented. The aim of this work is to estimate the potential of extracorporeal adsorption technique to remove these substances and to relate it to the porous structure of adsorbents. 

The staphylococcal toxin must be separated from food constituents and concentrated to detect trace amounts. The toxin is then identified by specific precipitation with antiserum as follows (1) the selective adsorption of the enterotoxin from an extract of the food onto ion exchange resins and (2) the use of physical and chemical procedures for the selective removal of food constituents leaving the enterotoxin in solution. More recently rapid methods based on monoclonal antibodies (e.g., enzyme-linked immunosorbent assay, reverse passive latex agglutination) have been developed for detecting very low levels of enterotoxin in food. 

The information available in the literature on the adsorption of mLR onto activated carbon indicates that, as with the adsorption of most microcontaminants, the removal efficiency is dependent on the type of activated carbon and the water quality conditions [70-72]. Newcombe and Nicholson [73] have reported a direct linear relationship between the adsorption of the toxin and the volume of pores between 2 and 50 nm, with a linear regression giving parameters = 0.97, P< 0.0001, and N = 9. 

In a broad sense, the medical applications of activated carbons are based on their powerful non-specific adsorption capacity luirivalled by any other material. They are used to remove undesirable and harmful substances - toxins - from the human body. These substances either enter the human body fiom the external environment via skin, eyes, breathing airways or with food and drinks, or they can be produced internally by the body itself due to organ malfunction, autoimmune diseases, infection or trauma. Considering ourselves as an inseparable part of the environment, both externally and internally generated toxins cause nothing else but pollution of our body, similar to the environmental pollution, which therefore has to be... 

Because of the unique gelling properties of alginates, they have been used as food thickeners, dental molds, and adsorption agents for removal of radioactive toxins (e.g., and In pharmaceutical and biomedical science, algi-... 

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