Optimization by factorial analysis of caprylic acid precipitation of non-immunoglobulins from hyperimmune equine plasma for antivenom preparation

► Caprylic acid concentration, pH and temperature are involved in the precipitation of hyperimmune equine plasma. ► Their influence was studied by factorial design. ► The best combination was 3% caprylic acid, 37 °C and plasma pH 4.9. ► Under these conditions, all immunoglobulins and only 0.1% albumin remained in the supernatant. ► After formulation, the antivenom obtained showed full lethality neutralizing activity and absence of protein aggregates.