Comparative study of activated carbon M1 of national production for use as an antidote

Abstract

Three activated carbons were studied USPXX, RPCh and M1. The
fallowing aspects were taken into account: physicochemical characterization,
CO2 adsorption at 273 K and phenobarbital adsorption in vitro from simulated
intestinal and simulated gastric fluids (SIF and SGF) USPXX and RPCh are
materials available for use as antidotes in the National Health Public System in
case of acute intoxicated patients by drugs overdoses. M1 is an activated carbon
of national production. Phenobarbital was selected because of high toxicological
incidence in Cuba as internationality. Physicochemical analyses reported
indicate that these activated carbons are according, to USP 27 pharmacopeia
parameters. Data were processed according to Dubunin-Radushkevich model
for CO2 adsorption isotherm data. It is demonstrated that the characteristic adsorption
energy and limiting amount filling the micropores found in M1 are in
agreement with both standards (USPXX and RPCh); it supports the resemblance
in the textural micropores structure. Determination of the differential heat and
differential entropy of adsorption in function of coverage degree (Na/NM) allowed
to establish a better thermodynamic similitude between M1 and RPCh
than USPXX.