Membrane plasma fractionation: effect of the surface area.

The influence of the surface area on the performance of plasma filters for dead-end mode of filtration is presented in this paper. Theoretical analysis of the dead-end filtration was performed and verified experimentally (using ENKA cellulose-diacetate PF-100 membranes) in respect to beta-lipoprotein. The theoretical model allows to optimize the course of the transmembrane pressure during plasma fractionation procedure in dependence of the surface area, initial concentration of macromolecules, total volume of the feed and membrane structure.

Stability of the lyophilized F(ab')2 fragments of horse tetanus antibodies isolated by affinity chromatography.

F(ab')2 fragments of horse tetanus antibodies were obtained from horse hyperimmune sera after peptic digestion. The digest was passed through a column of tetanus toxoid coupled with Sepharose 4B, F(ab')2 fragments were eluted with a solution of 5 mM HCl in 150 mM NaCl and the eluates were concentrated by ultrafiltration and lyophilized. Glycine and human serum albumin were used as stabilizing agents.

A versatile method for purification of diphtheria toxoid for immunization purposes.

Diphtheriae growth supernatant. The toxoid was quantitatively recovered from the immunosorbent in two fractions: the first in 0.005 M hydochloric acid and the second in 6' M urea containing 0.