Search results for "SORBENT"
showing 10 items of 635 documents
Exploring alternative hapten tethering sites for high-affinity anti-picoxystrobin antibody generation
2011
The relevance of the linker tethering site in haptens was investigated for antibody generation and immunoassay development. Three derivatives of the strobilurin fungicide picoxystrobin were synthesized with the same functionalized spacer arm located at three different positions. Protein conjugates of those haptens were employed as immunogens, and novel polyclonal antibodies were produced and characterized. All haptens afforded highly specific antibodies, but different affinities to the free analyte were observed among the obtained antisera. Next, competitive enzyme-linked immunosorbent assays were studied in several formats, and site heterology was confirmed as an effective strategy for det…
More about sampling and estimation of mercaptans in air samples
2013
[EN] Several strategies have been developed for sampling and determination of volatile thiols. The selectivity and sensitivity of the proposed methodologies are achieved by using a specific derivatizing reagent. The different procedures assayed are based on air sampling followed by derivatization of the analytes with OPA and isoleucine in alkaline solution. The derivatization products are separated and determined by liquid chromatography and fluorescence detection. To start, the derivatization conditions and stability of the derivates have been studied in order to establish the storage conditions. In general, the strategies studied consisted on trapping and detivatization the thiol compound…
Comparison of silica-based materials for organophosphorus pesticides sampling and occupational risk assessment.
2020
Abstract A novel air sampler has been designed containing a sorbent based on UVM-7 mesoporous silica doped with Ti. The sorbent has been applied for the determination of organophosphorus pesticides in occupational air, followed by gas chromatography with mass spectrometry detection. Thus, several silica materials with different structures (mesoporous UVM-7 and microporous xerogels) were synthesized, and modified with the addition of Ti and Fe. The structure of these materials was proved by transmission electronic microscopy, energy-dispersive X-ray, X-ray diffraction, nitrogen adsorption-desorption and UV–Vis and Raman spectroscopy. The potential of these materials for the retention of pest…
Development of a selective solid phase extraction method for nitro musk compounds in environmental waters using a molecularly imprinted sorbent
2013
A powerful analytical method for the determination of the family of the nitro musk compounds at trace level in environmental waters-river, sea, and water from a treatment plant-is presented. The method is based on the use of molecularly imprinted silica (MIS) as sorbent for solid phase extraction (SPE) used for the clean-up and the concentration step of the target analytes previous to their determination by gas chromatography-mass spectrometry. The optimized extraction procedure allowed extraction recoveries between 61% and 87% using the MIS. The comparison with a non-imprinted silica (NIS) sorbent, for which extraction recoveries between 8% and 26% were obtained, showed the high selectivit…
Macrophage Migration Inhibitory Factor Induces Inflammation and Predicts Spinal Progression in Ankylosing Spondylitis
2017
Objective: To investigate the role of macrophage migration inhibitory factor (MIF) in the pathogenesis of ankylosing spondylitis (AS). Methods: Patients who met the modified New York criteria for AS were recruited for the study. Healthy volunteers, rheumatoid arthritis patients, and osteoarthritis patients were included as controls. Based on the annual rate of increase in modified Stoke AS Spine Score (mSASSS), AS patients were classified as progressors or nonprogressors. MIF levels in serum and synovial fluid were quantitated by enzyme-linked immunosorbent assay. Predictors of AS progression were evaluated using logistic regression analysis. Immunohistochemical analysis of ileal tissue was…
Characterization of liver cytokeratin as a major target antigen of anti-SLA antibodies.
1990
Abstract Anti-SLA antibodies characterize a newly defined subgroup of patients with autoimmune chronic active hepatitis. The aim of the present study was the immunochemical characterization of the target antigen(s) of anti-SLA antibodies. Anti-SLA-positive sera were found to contain high titres of anti-cytokeratin antibodies. In immunoblotting analyses with 100 000 × g supernatants of human liver homogenates (S-100) these sera recognized various proteins with a molecular mass of 40–60 kDa. These proteins were also recognized by monoclonal anti-cytokeratin antibodies. Two-dimensional co-electrophoresis and immunoblotting analysis of S-100 and liver cytokeratins showed that anti-SLA antibodie…
CrELISA: a fast and robust enzyme-linked immunosorbent assay bypassing the need for purification of recombinant protein
2004
A multitude of antigens has been recently identified by screening of cDNA expression libraries derived from human tumors with autologous sera. Using a phage autoantibody assay and small panels of sera derived from cancer patients or controls it has been shown that some of these antigens display cancer-associated autoantibody responses. The diagnostic and prognostic significance of these potentially cancer-related autoantibodies remains unclear until large-scale assays are developed and serological data are available for hundreds of cancer patients and controls. The major bottleneck for the development of large-scale assays are the cloning, expression and the purification of each of the resp…
Haptoglobin interacts with apolipoprotein E and beta-amyloid and influences their crosstalk.
2014
Beta-amyloid accumulation in brain is a driving force for Alzheimer's disease pathogenesis. Apolipoprotein E (ApoE) represents a critical player in beta-amyloid homeostasis, but its role in disease progression is controversial. We previously reported that the acute-phase protein haptoglobin binds ApoE and impairs its function in cholesterol homeostasis. The major aims of this study were to characterize the binding of haptoglobin to beta-amyloid, and to evaluate whether haptoglobin affects ApoE binding to beta-amyloid. Haptoglobin is here reported to form a complex with beta-amyloid as shown by immunoblotting experiments with purified proteins, or by its immunoprecipitation in brain tissues …
Concurrent removal of Cr(III), Cu(II), and Pb(II) ions from water by multifunctional TiO2/Alg/FeNPs beads
2019
Abstract The use of multifunctional materials for water remediation is a modern approach where adsorption phenomena and heterogeneous photocatalysis can be applied for the removal of pollutants. Since the ideal remediation system should be able to remove both organic and inorganic pollutants, a crucial aspect to consider is the knowledge of operational parameters affecting the removal process, especially when heavy metal ions are present in concoction as in real systems. Given the proven efficiency of multifunctional TiO2/Alg/FeNPs magnetic beads for the removal of model organic pollutants, this study investigated the possibility to exploit such system also for the removal of mixed heavy me…
A calcined clay fixed bed adsorption studies for the removal of heavy metals from aqueous solutions
2021
Abstract A natural clay material from southern Tunisia was used as a low cost sorbent in a column-wise removal of metal pollutants. This is fundamentally important for a sustainable wastewater treatment strategy. This work has been performed within the framework of a project aiming to the valorization of natural geomaterials, from Tunisia, in several environmental applications. Column adsorption experiments were carried out for a better production of cleaner effluents and further understanding of the main mechanisms involved in the removal process, through a dynamic methodology, that would allow an industrial scale treatment. A calcined clay sample was used as an adsorbent for the removal o…