Curd-Sneed C D, Parks K S, Bordelon J G, Stewart J J
J Toxicol Clin Toxicol. 1987;25(1-2):1-11. doi: 10.3109/15563658708992609.
This study was designed to examine the in vitro adsorption of sodium pentobarbital by three activated charcoals. Solutions of sodium pentobarbital (20 mM) were prepared in distilled water and in 70% sorbitol (w/v). Radiolabeled (14C) sodium pentobarbital was added to each solution to serve as a concentration marker. Two ml of each drug solution was added to test tubes containing 40 mg of either Darco G-60, USP, or SuperChar activated charcoal. The drug-charcoal mixtures were incubated at 37 degrees C for O, 2.5, 5, 7.5 or 10 min. Equilibrium, indicated by a constant percentage of drug bound for two consecutive time periods, was established immediately for the aqueous mixtures and for Darco G-60 in sorbitol. The time to equilibrium was prolonged for USP (2.5 min) and SuperChar (5 min) in the presence of sorbitol. In the second series of experiments, solutions of sodium pentobarbital (1.25 to 160 mM) were prepared in either distilled water or sorbitol. Amount of drug bound by 10 to 320 mg of activated charcoal within a 10 min incubation period was determined. Scatchard analysis determined maximum binding capacity (Bmax) and dissociation constants (Kd) for each activated charcoal. In water, Bmax (mumoles/gm) was greatest for SuperChar (1141), followed by USP (580) and Darco G-60 (381), while the Kd's did not differ. Sorbitol did not change the Bmax or Kd of USP or Darco G-60, but the additive significantly decreased the Bmax (717) and increased the Kd for SuperChar (3.3 to 10.1 mM). The results suggest that relative binding capacity of activated charcoal is directly proportional to surface area, and that sorbitol significantly reduces sodium pentobarbital binding to SuperChar.
本研究旨在检测三种活性炭对戊巴比妥钠的体外吸附情况。戊巴比妥钠溶液（20 mM）分别用蒸馏水和70%山梨醇（w/v）配制。向每种溶液中加入放射性标记（14C）的戊巴比妥钠作为浓度标记物。将2 ml每种药物溶液加入含有40 mg Darco G - 60、USP或SuperChar活性炭的试管中。药物 - 活性炭混合物在37℃下孵育0、2.5、5、7.5或10分钟。对于水性混合物和山梨醇中的Darco G - 60，连续两个时间段内药物结合百分比恒定即表明达到平衡。在山梨醇存在的情况下，USP（2.5分钟）和SuperChar（5分钟）达到平衡的时间延长。在第二系列实验中，戊巴比妥钠溶液（1.25至160 mM）分别用蒸馏水或山梨醇配制。测定在10分钟孵育期内10至320 mg活性炭结合的药物量。通过Scatchard分析确定每种活性炭的最大结合容量（Bmax）和解离常数（Kd）。在水中，SuperChar的Bmax（微摩尔/克）最大（1141），其次是USP（580）和Darco G - 60（381），而Kd无差异。山梨醇未改变USP或Darco G - 60的Bmax或Kd，但该添加剂显著降低了SuperChar的Bmax（717）并增加了其Kd（从3.3至10.1 mM）。结果表明，活性炭的相对结合能力与表面积成正比，且山梨醇显著降低戊巴比妥钠与SuperChar的结合。
