Microtox system, a new approach to the safety evaluation of medical devices

Medical devices of both intra- and extra-corporeal applications may contain leachable toxicants that warrant routine testing using internationally recognized/practiced protocols. An in vitro Microtox system comprising a selected bioluminescence strain of bacteria-Photobacterium phosphorium which emits light as an end product of its respiration, is used to screen out toxicants from biomaterials/devices. A Microtox system was standardized and validated in our laboratory conditions. Our experiences with extract of pyrogenic cardiotomy reservoir, blood filter and systemically toxic (in mice) Barium methacrylate (monomer), and CIBA epoxy polymer materials established a positive correlation with Microtox system. Hence, the Microtox system gives adequate evidence as an alternative in vitro method to evaluate the toxicity of biomaterials and medical devices.