Agarose derivatives

Sepharose CL gels of Pharmacia Biotech are cross-linked agarose derivatives with cross-links formed by 2,3-dibromopropanol. Compared to pure agarose, the cross-linking improves chemical and physical resistance of the... 

TABLE 16.6 Producers (Pharmacia Biotech) Specification of Fractionation Ranges of 2,3-Dibromopropanol Cross-Linked Agarose Derivative-Based Sepharose CL Gels... 

Wilchek [51] has described poly-DL-alanine poly-L-lysine agarose derivatives. These gels offer the advantage of introducing a hydrophilic spacer and thus reducing non-specific hydrophobic interactions with the spacer. 

The most effective supports were those prepared by the attachment of 17/3-oestradiol 17-hemisuccinate to agarose derivatives containing albumin or the poly-L-lysine or poly-DL-amine spacers. Non-specific adsorption of non-receptor proteins was reported to be minimal and the described procedures gave purification between 10000- and 100000-fold with 30 to 50% yields in a single step. 

The possibility of inter-ionic and hydrophobic forces acting together to affect separation in some cases is likely. In a further publication, Shaltiel and Er-El [164] prepared a homologous series of co-aminoalkyl-agarose derivatives of the type, Sepharose-NH(CH2)n-NH2. When an extract of rabbit muscle was subjected to chromatography on these derivatives glycogen synthetase was not bound to n = 3 gels but was retained on 4-... 

AcrylAide (PHC Marine Colloids), an olefinic agarose derivative, which permits gels on polyester supports to be dried at 60°C without the use of vacuum. Gel polymerization is usually initiated by ammonium persulphate and N,N,N, N -tetramethylethylenediamine (TEMED). Riboflavin can be used for uv-activated polymerization but this reaction is comparatively slow (1 ). Careful control of polymerization conditions is essential for reproducible results. 

Ion exchange cellulose, polydextran and agarose derivatives are used for the LC separations of biopolymers [19,20]. In some cases (meth)acrylate derivatives can also be applied for such a purpose. LC of other organic substances (various bases and acids, amino acids and peptides, nucleosides and nucleotides, sugars, etc.) can be realized using ion exchange resins (cf.. Ref. 5, Tables 13.1-13.9, and Ref. 6, Tables... 

Blanco RM, Guisan JM (1988) StabiDzation of enzymes by multipoint covalent attachment to agarose-aldehyde gels. Borohydre reduction of trypsin-agarose derivatives. Enzyme Microb Technol 11 360-366... 

Purification of a threonine-sensitive, aspartokinase-homoserine dehydrogenase complex comparisons of the adsorptivities of agarose derivatives as a function of the length of the alkyl chain 60... 

Assessment of the relative suitabilities of agarose cyclic imidocarbonate and other agarose derivatives as affinity-chromatography matrices... 

Evidence has been reported for the presence of inhibitors of porcine pancreatic a-amylase in rye and wheat. The inhibitors were isolated by affinity chromatography on the agarose derivative-immobilized enzyme. The location in the seed, molecular properties, and biological role of proteinaceous inhibitors of a-amylase in wheat have been reviewed. Inhibition specificity of albumin inhibitors and structural features essential for interaction with inhibited amylases were also examined. The possible significance of these naturally occurring inhibitors in relation to their presence in foods in active form was described. 

The temperature at which affinity chromatography is performed has been shown to be critical for the isolation of ribosomes on heparin-agarose derivatives the ribosomes are retained at 4 °C but do not bind at 22... 

Using an agarose derivative of anti-(pregnancy zone protein) antibody, the use of an automated immunospecific affinity chromatography system for continuous use has been demonstrated for the purification of pregnancy zone protein. The automated system includes time-controlled sample application, washing and elution steps, and automatic dialysis of eluted fractions. 

Tannic acid treatment of the S. flavochromogenes culture filtrate to yield a tannin-pullulanase complex which is adsorbed to triethylaminoethyl-cellulose Covalent reaction with a commercially available organomercurial agarose derivative... 

The affinity chromatography of a-D-acetamidodeoxygalactosidase and j3-d-acetamidodeoxyglucosidase on an agarose derivative that had been allowed to react with diazophenyl oxamate has been investigated. The binding of the enzymes to the matrix, which hitherto has been considered to be specific for neuraminidase, is now thought to be non-specific, and it is doubtful whether the association is of a true affinity nature. 

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