Trapping urea in a wearable artificial kidney (WAK)

One of the kidneys’ functions is filtering the blood and removing waste products such as uremic toxins. For some Kidney failures, hemodialysis is being used to prevent accumulations of waste products in the body. In that process, the patient’s blood flows through narrow semi-permeable tubes, in order to allow waste products to diffuse across a polysulfone (Psf) membrane to the surrounding dialysate, which is sent to the waste. According to recent studies, continuous but slow dialysis reduces death and increases the quality of life among patients. For this purpose, the system (Wearable Artificial Kidney- WAK) was developed to mimic the kidney function by trapping urea and other waste products from the dialysate, i.e. the idea is to recycle it. The most successful attempt to trap urea includes breaking it into ammonia and trapping the ammonia using zirconium phosphate, but this system fails under the WAK, since is even small amounts of ammonia returns to the blood, it will be very toxic to the human body. Here we will present some preliminary results for materials, which traps urea from the dialysate in physiological conditions (pH=7, aqueous solution) allowing to recycle it.