SURFACTANT-MODIFIED POLY(VINYL CHLORIDE) MEMBRANES AS BIOCOMPATIBLE INTERFACES FOR AMPEROMETRIC ENZYME ELECTRODES

Membranes constituted from polymers of differing intrinsic chemical co mposition as well as poly(vinyl chloride) (PVC) membranes variously mo dified with plasticising agents were assessed as potential blood conta cting interfaces for enzyme electrode use. PVC membranes modified with the nonionic surfactants Tween 80 or Triton X-100 and anionic bis(2-e thylhexyl)hydrogenphosphate exhibited superior biocompatibility over t he commercially available porous polycarbonate and Cuprophan haemodial ysis membranes. A cationic surfactant (tricaprylylmethylammonium chlor ide)-modified PVC membrane exhibited the worst biocompatibility. The o bserved trends in biocompatibility assessed both in terms of sensor re sponse changes and scanning electron surface microscopy were rationali sed on the basis of membrane surface topography as well as the modifyi ng effect of additive plasticiser.