The development of synthetic polymers that resist encrustation on exposure to urine.

The consequences of long-term exposure of synthetic materials to urine have prevented the development of alloplastic replacement of diseased or damaged parts of the urinary tract. Similarly, urethral and ureteric catheters require regular replacement if the complications of encrustation and blockage are to be avoided. The mechanism of encrustation is not understood completely and thus it is unclear why certain materials appear better able to resist encrustation. This study has involved the development of a new encrustation model to provide a reproducible and quantitative assessment of the susceptibility of polymers to encrustation. This model will allow beneficial characteristics of co-polymer design to be recognised, with the aim of finding new materials that are tolerant of exposure to urine. Results of co-polymers examined show that the incorporation of fluorine-containing components confers significant resistance to the formation of encrustation. It is suggested that the physico-chemical properties of polymer surfaces may be important determinants of resistance to encrustation.