Search results for "Sorbent"
showing 10 items of 635 documents
Immunogenic antigens of the eel pathogen Vibrio vulnificus serovar E.
2003
Abstract The immunogenic antigens of Vibrio vulnificus serovar E were investigated in the eel. Fish were vaccinated by immersion with Vulnivaccine (V), revaccinated 2 years later by intraperitoneal injection (RV) and bath infected 15 days post-revaccination (RVI). The specific immune response in serum was followed in all groups, and selected sera were used for immunostaining of surface (SA) and extracellular antigens (ECA). Bacteria were grown in iron-rich (TSB and MSWYE) and iron-poor media (TSB and MSWYE plus human transferrin (TSB-T and MSWYE-T)) as well as eel serum (ES), and their SA and ECA were extracted and electrophoretically analysed. Cells grown in MSWYE-T and ES presented the sa…
Electropherotypes, subgroups and serotypes of human rotavirus strains causing gastroenteritis in infants and young children in Palermo, Italy, from 1…
1990
During 1985-89, an epidemiological survey was conducted in Palermo, Sicily (Southern Italy) on group A human rotavirus (HRV) strains which cause gastroenteritis in infants and young children. Two hundred and thirty eight HRV strains were characterized for subgroup and serotype using monoclonal-antibody-based ELISA systems, and for electropherotype using polyacrylamide gel electrophoresis. Subgroup II strains were largely predominant, constituting 218/238 of the positive stool samples (91.6%). Among the serotypes, 192/238 strains (80.7%) were serotype 1 and 16 strains (6.7%) were serotype 4; serotype 2 circulated intermittently and serotype 3 was nearly absent (only one subgroup I strain was…
Serotyping and genotyping of encapsulated Escherichia coli K1 sepsis isolates with a monoclonal IgG anti K1 antibody and K1 gene probes
1987
Among infectious diseases caused by E. coli the capsular type K1 plays a predominant role. E. coli K1 isolates account for 80% of cases of E. coli neonatal meningitis and 30% of E. coli sepsis strains. Serotyping of K1 strains has conventionally relied upon the use of K1-specific bacteriophages or serum agar methods with polyvalent anti K1 serum. In the study present here, 187 E. coli sepsis isolates have been analysed for production of the K1 antigen using K1 phages, K1 serum agar plates and Latex agglutination and ELISA using an IgG2a anti K1 monoclonal antibody. In total, 33 sepsis isolates (about 18%) were identified as K1 positive, with three of these strains proving negative in all te…
The region 0.7615-0.796 m.u. of the HSV-1 genome determines suppression of humoral antibody formation against herpes simplex virus.
1991
The influence of genetic properties of parts of the HSV-1 genome on suppression of humoral antibody formation was investigated by using intratypic recombinants. The deleted strain HFEM (HSV-1) induces suppression. The MluI DNA fragment (coordinates 0.7615–0.796 m.u.) derived from the antibody inducing strain F1 (HSV-1) was transfected into the deleted strain HFEM to produce the recombinant virus R-MlCI and shown to restore antibody formation, as demonstrated by neutralization- and ELISA-tests. The intratypic recombinant viruses R-15, R-19 and R-26, produced by transfection of the Bam HI DNA-fragment B (0.738–0.809 m.u.) of strain Fl into the deleted strain HFEM, resulted in antibody formati…
Determination of benzomercaptans in environmental complex samples by combining zeolitic imidazolate framework-8-based solid-phase extraction and high…
2020
[EN] In this work, the synthesis of zeolitic imidazolate framework-8 (ZIF-8) crystals and their subsequent application as effective sorbents for extraction and preconcentration of several benzomercaptans from environmental complex samples is described. These materials were prepared by solvothermal approach varying the concentration of n-butylamine modulator to modify the surface of the metal-organic framework. The resulting materials were characterized by scanning and transmission electron microscopy, powder X-ray diffraction and Fourier transform infrared spectroscopy. The ZIF-8 material that gave the best features was selected as extractive phase and the influence of various parameters (s…
Enhancing extraction performance of organophosphorus flame retardants in water samples using titanium hierarchical porous silica materials as sorbent…
2021
Abstract A sorbent for the extraction of organophosphorus flame retardants has been proposed, based on UVM-7 (University of Valencia Materials) mesoporous silica doped with titanium. Designed cartridges have been applied to the extraction and preconcentration of flame retardants in water samples, followed by gas chromatography coupled to a mass spectrometry detector. Firstly, UVM-7 materials with different contents of titanium were synthesized and characterized by several techniques, thus confirming the proper mesoporous architecture. The potential of these materials was assessed in comparison with their morphological properties, resulting Ti50-UVM-7 the best solid phase. Several extraction…
Utilisation of barium-modified analcime in sulphate removal: Isotherms, kinetics and thermodynamics studies
2017
Abstract Analcime and commercial zeolite were employed as a precursor for preparing sorbent material for SO42− removal over barium modification. Three sorbents were prepared: barium-modified analcime (ANA-Na-Ba), barium-modified acid-washed analcime (ANA-Ac-Na-Ba) and barium-modified zeolite (ZSM5-Na-Ba). Of the prepared materials, ANA-Ac-Na-Ba was the most efficient sorbent material for SO42− removal, with a maximum sorption uptake of 13.7 mg g−1 at room temperature. Batch sorption experiments were performed to evaluate the effect of initial pH, initial SO42− concentration, sorbent dosage, temperature and contact time of sorption. Several isotherms were applied to describe the experimental…
Over-evaluation of total flavonoids in grape skin extracts containing sulphur dioxide
2015
Abstract Sulphur dioxide (SO 2 ) proved to increase absorbance at 280 nm of grape skin and seed extracts containing it, diluted with ethanol–HCl to assess total flavonoids and anthocyanins in the same analysis. Additional absorbance at 280 nm was also observed in acetone:H 2 O extracts, if the acetone had not completely evaporated before the extracts were diluted with a solvent. Flavonoids were correctly quantified in the extracts when SO 2 or acetone were removed by solid-phase extraction with a C 18 RP as sorbent and methanol as eluting solvent.
Comments on surface structure analysis by water and nitrogen adsorption
2004
Specific surface area and pore size distribution are determined usually from adsorption isotherms at low temperatures using nitrogen or noble gases. These are not absolute parameters and the measuring methods are fraught with serious difficulties. General problems of sorption measurements and recent developments are discussed. To obtain information for practical purposes these measurements need to be supplemented by investigations of the sorbate/sorbent system used in practice. Results of the measurement of nitrogen and water vapour adsorption on different materials are compared.
Dispersive solid-phase extraction based on oleic acid-coated magnetic nanoparticles followed by gas chromatography-mass spectrometry for UV-filter de…
2011
Abstract A sensitive analytical method to concentrate and determine extensively used UV filters in cosmetic products at (ultra)trace levels in water samples is presented. The method is based on a sample treatment using dispersive solid-phase extraction (dSPE) with laboratory-made chemisorbed oleic acid-coated cobalt ferrite (CoFe 2 O 4 @oleic acid) magnetic nanoparticles (MNPs) as optimized sorbent for the target analytes. The variables involved in dSPE were studied and optimized in terms of sensitivity, and the optimum conditions were: mass of sorbent, 100 mg; donor phase volume, 75 mL; pH, 3; and sodium chloride concentration, 30% (w/v). After dSPE, the MNPs were eluted twice with 1.5 mL …