In-vitro adsorption studies of isoniazid

In-vitro experiments were performed to investigate the extent of adsorption of isoniazid to activated charcoal and locally produced activated carbon black (N220) and to explore the effect of varying pH on this adsorption. The results of the study indicated that activated charcoal and activated carbon black adsorbed isoniazid effectively. Adsorption was dependent upon the quantity of charcoal used. With charcoal quantity at 0.5 g, adsorption was virtually completed within 60 min. The mean or composite adsorption capacity of activated charcoal and activated carbon black (microgram ml-1 of charcoal) were 325 and 278, respectively. The result of adsorption isotherms indicated no change in binding capacity of the drug from solutions of different pH.