Monoclonal antibody binding adsorption

Immobilized histidine on agarose beads by means of aminohexyl spacer arm has also been utilized to purify polyclonal217 and monoclonal antibodies.218 Adsorption of IgG on histidine-agarose occurs in the presence of 25 mM Tris-HCl buffer, pH 7.4, and elution is achieved using a solution of 0.2 M sodium chloride in the same buffer. In described conditions the binding capacity of antibodies was about 11 mg/mL of resin and purity of separated antibody was estimated by the authors at around 98% when combined with ethanol precipitation. Dissociation constant was also determined and reported between 2.4 X 10-6 and 4.6 X 10-6 M. 

Wu Y, Simonovsky FI, Ratner BD, Horbett TA. The role of adsorbed fibrinogen in platelet adhesion to polyurethane surfaces a comparison of surface hydrophobicity, protein adsorption, monoclonal antibody binding, and platelet adhesion. J Biomed Mater Res A 2005 74(4) 722-38. 

Clearly specific antibodies, and particularly monoclonal antibodies, may be very useful in probing the properties of adsorbed proteins. Specific antibodies have been used to probe the structure of antigens in solution 88). Consider the adsorption of a simple protein with a small number of reasonably well-defined epitopes (surface sites with antibody binding activity), as in Fig. 19. Clearly epitopes E and A are not accessible for binding, while B, C, and D would be sterically accessible. One could also envision a conformational change upon adsorption which produces an epitope... 

Direct, nonsurfactant-mediated immobilization of metallothionein proteins [207-209] and streptavidin [210] at MWCNTs has also been carried out, the hydro-phobic regions of the proteins probably being responsible for the adsorption. Specific affinity binding of proteins to unmodified SWCNT sidewalls was demonstrated by the adsorption of monoclonal antibodies, IgG, specific for C60 fuller-enes, in aqueous solution. The affinity binding originated from the structural similarity of the tube sidewall graphite network and the C(M fullerene [221]. It was shown that the specific binding site of the IgG antibody is a domain of hydrophobic amino acids. 

Thiophilic adsorption chromatography has been described for the purification of murine monoclonal antibodies from hybridoma cell culture containing fetal bovine serum.154 Due to the very low concentration of immunoglobulins in cell culture supernatants, binding capacity remains modest in spite of the presence of 0.5 to 1 M potassium sulfate. Further developments of this technology described by Nopper et al.155 indicated that thiophilic sorbents could be modified in their structure to increase the specificity and the binding capacity. 

The nonspecific (physical) adsorption and covalent binding of CD-95 monoclonal antibodies on the surface of Fe304/HA, Fe304/PAA, and Fe304/ -APS nanocomposites, respectively, were investigated. 

Direct, nonsurfactant-assisted immobilization of metal-lothionein proteins and streptavidin has also been pursued on MWNTs. The hydrophobic regions of the proteins are probably important for the adsorption on the surfaces of CNT. A monoclonal antibody, specific for Cso fullerenes, could also be direaly bound to SWNTs. It has been thus indicated that the binding site of this IgG antibody is a domain of hydrophobic amino adds. The mechanism of protein immobilization on surfaces of CNTs may be the nucleophilic... 

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