Chemical sorbents: official guidelines and experimental approach.

To evaluate the biocompatibility of an anionic exchange resin with active group trimethylammonium and charged with chloride ions an experimental study was performed with different tests to determine cytocompatibility, acute systemic toxicity, intracutaneous reactivity, allergic sensibilization, haemocompatibility and release of acetone, dichloromethane, quaternary amines and heavy metals (Pb, Cu, Cd) in eluate. Thus an anionic exchange resin can link all anionic substances; an ex vivo study on the participation of the dissociated sodic heparin in the anionic exchange was also conducted. In fact every time an extracorporeal circuit is made an anticoagulant must be administered to the patient and the removal of the drug could cause serious haemocoagulative problems. The results of the study showed a high biocompatibility of the resin that did not cause different significant reactions in comparison with negative control substances. The coating of the resin with poly-hydroxy-ethyl methacrilate with a separation phase technique avoided heparin removal from blood. Therefore adjustment of the dosage may not be necessary during further in vivo experiments. Future researches aiming to evaluate the the effectiveness and the biocompatibility of the sorbent in a living being will be performed in the next steps of the study.