title: Adsorption-desorption of recombinant hepatitis B surface antigen (r-HBsAg) from P. pastoris on a diatomaceous earth matrix: Optimization of parameters for purification.
abstract: Recombinant hepatitis B surface antigen (r-HBsAg) produced in yeast is adsorbed on a diatomaceous earth matrix for purification purposes. A pH dependence in the adsorption-elution behavior was found. The capacity of celite (Hyflo Super Cei) for adsorbing r-HBsAg increased with decreasing pH. Nonspecific proteins were also adsorbed, but a low pH dependence was found. Elution from the matrix was performed using a basic pH buffer, in which r-HBsAg is more specifically adsorbed/desorbed than contaminant proteins, permitting the purification of the r-HBsAg. A pH of 4.0 was used for adsorption and pH 8.2 was used for desorption. The described protocol allows a purification factor between three- and fivefold with respect to contaminant proteins and sixfold with respect to contaminant DNA. Finally, the adsorption step was successfully scaled-up for production purposes.
authors.affiliation: Center of Genetic Engineering and Biotechnology, C. Havana, Cuba.
authors.forename: A
authors.initials: A
authors.lastname: Agraz
authors.forename: Y
authors.initials: Y
authors.lastname: Quiñones
authors.forename: N
authors.initials: N
authors.lastname: Expósito
authors.forename: F
authors.initials: F
authors.lastname: Breña
authors.forename: J
authors.initials: J
authors.lastname: Madruga
authors.forename: E
authors.initials: E
authors.lastname: Pentón
authors.forename: L
authors.initials: L
authors.lastname: Herrera