Removal of endogenous and exogenous toxins by a microencapsulated absorbent

Abstract

Three types of microencapsulated activated charcoal were tested. Unlike activated charcoal in the free form, the microencapsulated form did not give off embolizing particles. Heparin-complexed or albumin-coated collodion microencapsulated activated charcoal did not lower the arterial platelet level. Albumin-coated collodion microencapsulated activated charcoal was more efficient than the heparin-complexed form in lowering the blood creatinine level.

First Design and Clinical Use in Patients of Surface Modified Sorbent Hemoperfusion Based on Artificial Cells for Poisoning, Kidney Failure, Liver Failure and Immunology

“…While carrying out research on artificial cells (Chang, 1964), my theoretical analysis showed artificial cells can be the basis of a very simple and inexpensive detoxifier that can be more effective than the standard hemodialyser (Chang, 1966). While continuing with basic research on the other aspects of artificial cells, I spent a major part of my early 15-year research career developing this idea followed by successful clinical trials and routine use in patients (Chang, 1966(Chang, , 1969a(Chang, , 1971d(Chang, , 1973a(Chang, , 1974c(Chang, , 1974h, 1975i, 1976g, 1977b.…”

“…Thus, Professor Kolff, the inventor of the artificial kidney, wrote the Canadian Medical Research Council that this approach should be extensively supported. Locally, McGill's human ethics committee having reviewed in detail all our preclinical safety and efficacy animal studies (Chang, 1969a(Chang, , 1972aChang and Malave, 1970;Chang et al, 1971a) approved the use of this device for clinical trials at McGill's teaching hospitals. At that time this was a very new idea, and although physicians were very supportive, they were concerned about liability and thus not ready to carry out this procedure in clinical trials in patients.…”

“…Furthermore, the flexibility of the ultrathin membrane increases flow resistance and also packing and obstruction at the exit port of the hemoperfusion device. A more successful method is to coat the ultrathin membrane directly onto activated charcoal granules (Chang, 1969a). This way, there is no breakage of the ultrathin membrane, no increase in flow resistance and no obstruction to flow.…”

“…1.20) (Chang 1969a). This is initially used to increase the blood compatibility of the adsorbent artificial cells for hemoperfusion (Chang, 1969a).…”

Removing Substances from Blood by Affinity Chromatography

“…The problems of blood compatibility and particle emboli have been largely overcome by microencapsulation with nylon, methacrylate, or cellulose nitrate (22)(23)(24), and hemoperfusion over microencapsulated charcoal has been effective in the clinical management of the uremic syndrome (25). Drugs such as acetylsalicyclic acid, acetaminophen, barbiturates, and glutethimide, which show some protein binding, have also been removed from plasma in vitro (26,27) and in vivo (28)(29)(30)(31)(32) by this technique.…”