Catheters are used in clinical urological practice when other methods of managing obstruction and incontinence fail. Ideally, they should resist bacterial colonization and encrustation of calcium and magnesium mineral deposits. The catheters presently in use suffer from the above two problems causing infections, strictures and pain to the patients. The encrustation is caused by urease producing bacteria: the action of urease on urea results in ammonia production, resulting in increased urine pH. Alkaline pH causes the precipitation of calcium and co-precipitated magnesium products. Ideas are presented in this proposal for covalently attaching some powerful reactive organic functionalities that will a) deactivate urease, b) prevent the calcium and magnesium phosphate precipitation even if the pH rises and c) prevent bacterial adherence. These organic functionalities will be incorporated on the surface layers of the catheter. Different modified surfaces will be tested in an in vitro encrustation chamber using human urine in the infected and non-infected modes for extended periods of time. The results of these experiments will be used to develop an encrustation resistant urological catheter.
