To begin plasmapheresis, whole blood will be taken from your arm. The whole blood is then drawn by the automated machine into a centrifuge that spins, causing the plasma to separate from the red blood cells.
As long as 30 days. It will last longer in glass containers and in the refrigerator or a dark place but can be stored in plastic bottles because the alkaline water will not leach like R.O. or distilled water.
Urine specimens need to be examined within 2 hours. Urine that is left to standing too long becomes alkaline because bacteria begins to split the urea contained in urine into ammonia. Visualization of urine and other tests are inaccurate if the pH of the urine specimen has become highly alkaline.