Stability Determination of Recombinant Echinococcus Granulosus Antigen B Kit by Physical and Bacteriostatical Methods

Cystic hydatidosis disease (CHD) is a common disease of human and animal caused by contamination with the metacestode stage of echinococcus granulosus. The disease causes cyst in tissue body of patients. Antigen B is one of the important antigens in liquid cyst. Expressed and purified recombinant antigen of echinococcus granulosus was used as antigen in ELISA (Enzyme-linked immunosorbent assay) method. The handmade kit was studied with physical and bacteriostatical methods. Physical stability was assessed with accelerated stability test (Arrhenius equation). First، numeral negative and positive samples were evaluated; then، the kit was exposed in special temperatures and times; afterwards، the samples were evaluated again and compared with the first evaluation. Proclin300، Soduim azide and Bacillus subtilis were chosen in bacteriostatic method. Different concentration of bacillus and different percents of preservatives were added to solutions of the kit. Growth of bacteria was evaluated and the least percent of preservatives that had the most effect of bacteriostatic was determinated. According to stability test، the handmade kit had one-year stability and do not have stability for two years in the 2-8ºC tempreture. Sodium azide had destructive effect on solutions of the kit; but، proclin300 with the concentration of 0. 05% was appropriate for solutions. Stability and bacteriostatic methods showed that the handmade kit can be maintained in 2-8ºC with significant activity.