Combined Effects of Activated Carbon and pH on Ionic Composition and 2,4-D Availability in a Tissue Culture Medium, 1997 Biological Sciences Symposium Proceedings

Activated carbon (AC) is added to tissue culture medium, often giving positive results. Two different activated carbons have been found to give different success rates in tissue cultures. The two carbons have been characterized using several different techniques with the goal of correlating character with impact on medium composition. Ash %, point of zero charge (PZC), and apparent surface area, showed the greatest differences. Medium pH was found to vary with AC type, and preparation technique. The combination of AC and medium pH (ranging from pH 4.8 to pH 6.8) could significantly alter the ionic composition of the medium, resulting in decreased Cu (-90%), Zn (-50%), Fe (-50%) and Mn (-60%) and increased Mg (+50%). The sorption of 2,4-D varied with apparent surface area (BET)

and system pH: together these factors resulted in nearly 50% differences in sorption capacity. These findings may help to explain some of the contradiction in the literature regarding the benefits of including AC in tissue culture medium.