H. E. Bertorello

Preparation of adsorbents applicable to pseudobiospecific ligand affinity chromatography using different spacers and ligands

Abstract In this paper, a series of different adsorbents for pseudobiospecific ligand affinity chromatography is presented. They were obtained using ligands as histidine, Cu 2+ - or Zn 2+4 -chelating iminodiacetic acid and Cibacron Bhue F3GA dye, attached to poly(butadiene-hydroxyethylmethacrylate) (PB-HEMA) matrix. The histidine and metal-iota-chelating iminodiacetic acid were attached on matrix through epichlorohydrin (ECH) or 1,4-butanediol diglycidyl ether (BDGE) as spacers and activators, while dye was directly bound onto the matrix.

Preparation and characterization of new biospecific adsorbents with fatty acids as ligands, usable to retain bovine serum albumin

The property of albumin to bind long-chain fatty acids was exploited for the development of adsorbents containing them as ligands to isolate that protein. The synthesis of gels containing oleic or ricinoleic acids bonded to a synthetic matrix and the capacity to retain albumin are presented. The probable retention of other proteins (gelatin and lysozyme) was also tested.

Synthesis of cross-linked polymers by reaction of sucrose and diepoxide monomers: Characterization and nuclear magnetic resonance study

The synthesis of a new cross-linked structure, with sucrose and diepoxide monomers, possessing the properties of a highly swellable hydrogel polymer is reported. Characterization studies of its structure and water effects were carried out in dried and hydrated samples by CP-MAS 13C n.m.r., by wide-band 1H and 2H n.m.r. and by differential thermal analysis. The results indicate that the sample is completely amorphous and disordered, that methyl groups are present and that there is strong water structuring due to hydrogen bonding, with an absence of free water at low levels of hydration. Two processes are manifest in the temperature dependence of the 2H line width.

13C NMR study of the structure of the hydrogel polyester of sucrose methacrylate (Sucro-Gel H-70)

SummaryA 13C NMR study of four samples of poly(sucrose methacrylate) differing in molecular weight and degree of crosslinking was performed to determine their structure. It was concluded that Sucro-Gel H-70 polymer consists mainly of monomer units of isomeric monoesters principally esterified in C6 C6′ C4 position and forming atactic helical chains with some crosslinks due to the presence of substituted monomer units.

A study of the chelation behavior of heavy metal ions using a new synthetic support : PAS-GLUT

Abstract A synthetic gel obtained by bulk polymerization of sucrose acrylate and incorporating glutaraldehyde crosslinking was used to remove heavy metal ions from aqueous and organic solutions through chelation. The influences of pH, concentration, swelling index, temperature, and solvent on the gels chelation tendencies towards CuCl2, Pb(NO3)2, HgCl2, Ca(OH)2, NiSO4, UO2Ac2 and Hg(AcO)2 are described in this paper.

Preparation and properties of polymers of carboxylated polybutadiene containing sucrose

SynopsisThis paper describes the attachment of sugar (sucrose) to low molecular weight carboxylated polybutadiene (esterification) to produce a new class of synthetic polymers. The products were characterized by I.R. and N.M.R. spectroscopy. Their thermal and thermooxidative characteristics are discussed from DSC and TGA in nitrogen and air. The polyurethanes obtained were studied.

Synthesis and characterization of biospecific adsorbents containing glucose, usable to retain concanavalin A

Abstract The synthesis and characterization of poly(butadiene-hydroxyethylmethacrylate-epichlorhydrin- d -glucose) (PB-HEMA-ECH- d -Glu) and poly(butadiene-hydroxyethylmethacrylate-epichlorhydrin- l -glucose) (PB-HEMA-ECH- l -Glu) hydrogels are presented. The applicability of these products was studied in order to establish their stereospecific capacity in the retention of concanavalin A.

Reaction Between 3,3′-dibromo-4,4′-difluorobiphenyl and n-butyllithium

Abstract The reaction between 3,3′-dibromo-4,4′-difluorobiphenyl and n-butyllitium is described. The organolithium compound formed was carboxylated to give 4,4′difluoro-3,3′-biphenyldicarboxylic acid in good yield. The formation of dehydroaromatic compounds by elimination of lithium fluoride is proposed on the basis of observed addition reactions with furan and autocondensation reactions which lead to macromolecules.

Reactions and thermal decomposition of organolithium compounds derived from 4,4′-dibromooctafluorobiphenyl

Abstract The lithiation of 4,4′-dibromooctafluorobiphenyl with n-butyllithium to yield 4,4′-dilithiooctafluorobiphenyl and 4-lithio-4′-bromooctafluorobiphenyl as a by-product under various conditions is described. It is proposed that thermal decomposition of the lithiated products formed at low temperatures (−80° to −90°) leads to products originating principally by nucleophilic displacement reactions, while rapid thermal decomposition, after metal-halogen interconversion at temperatures of 0°, leads principally to products originating by elimination reactions. The intermediacy of benzyne species is proposed on the basis of observed addition reactions with furan to give the adduct 1,1′,3,3′,4,4′-hexafluoro-5,8,5′,8′-tetrahydro-2,2′-binaphthyl 5,8,5′,8′-diepoxide.

Preparation of new gels derived from poly(sucrose acrylate) with immobilized Cibacron Blue and their application in affinity chromatography

SummaryNew pseudoaffinity chromatography supports were prepared and characterized from poly(sucrose acrylate) crosslinked with MDI or TDI and Cibacron Blue dye as ligand. Blue gels were useful in the retention of albumin and the results are reported.