NEW MATERIALS FOR URINARY CATHETERS AND STENTS

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, LEADING TO INCREASED URINE PH. ALKALINE PH CAUSES THE PRECIPITATION OF CALCIUM AND CO-PRECIPITATED MAGNESIUM PRODUCTS. THIS PROJECT WILL COVALENTLY ATTACH SOME POWERFUL REACTIVE ORGANIC FUNCTIONALITIES THAT WILL (1) DEACTIVATE UREASE, (2)PREVENT THE CALCIUM AND MAGNESIUM PHOSPHATE PRECIPITATION EVEN IF THE PH RISES, AND (3) PREVENT BACTERIAL ADHERENCE. THESE ORGANIC FUNCTIONALITIES WILL BE INCORPORATED ON THE SURFACE LAYERS OF THE CATHETER. DIFFERENT MODIFIED SURFACESWILL BE TESTED IN AN IN VITRO ENCRUSTATION CHAMBER USING HUMAN URINE IN THE INFECTED AND NONINFECTED MODES FOR EXTENDED PERIODS OF TIME. THE RESULTS OF THESE EXPERIMENTS WILL BE USED TO DEVELOP AN ENCRUSTATION-RESISTNANT UROLOGICAL CATHETER.