Since the molecular weights of acetate, bicarbonate and urea are almost identical, the dialysance of these substances are expected to be same. To know if this hypothesis is correct, we determined the dialysances of these substances both in acetate and bicarbonate dialysis. Contribution of the difference of membrane quality and effective surface area was also evaluated Dialysis was performed at the conditions of Ob 200ml/min, Od 500ml/min, TMP 200mmHg and the dialysis temperature 37°C.
Dialysances of bicarbonate and acetate showed a difference according to membrane materials and effective surface area. Transfer rates of bicarbonate exceeded in Cuprophane, EVA and large surface area dialyzer than in otherss. Acetate dialysance was inferior to bicarbonate and urea dialysance. This difference was not accounted for in terms of molecular weight. The transfer co-efficient of acetate showed a tendency to be low in large surface area dialyzer.
