Christiansen E
Scand J Urol Nephrol. 1976(30 Suppl):8-18.
The absorption capacity of the REDY cartridge was investigated exclusively by in vitro experiments. The maximum absorption capacity for urea, phosphate, creatinine, and urinc acid, was found to be respectively 55 g, more than 4 g (phosphorus), 10 g, and more than 7,5 g. The maximum absorption rates of the same substances were found to be 600-800 mg/min., more than 33 mg/min., more than 170 mg/min., and 13 mg/min. respectively. The ability of the cartridge to absorb urea was found to be practically unaffected by 2 mmol of copper and 7 mmol of zinc, and to be unaffected by supraphysiological concentrations of lithium. The amount of exchangeable cations was determined for three cartridges, and found to be 6100, 3800, and 7200 mmol. The cation exchanger was found to act as a buffer, giving the whole cartridge a buffering capacity of 0,6 mol. Of the layers of cation exchanger, anion exchanger, and activated charcoal, only the latter was found to be able to bind urea.
仅通过体外实验研究了REDY柱的吸附能力。发现其对尿素、磷酸盐、肌酐和尿酸的最大吸附量分别为55克、超过4克（磷）、10克和超过7.5克。相同物质的最大吸附速率分别为600 - 800毫克/分钟、超过33毫克/分钟、超过170毫克/分钟和13毫克/分钟。发现该柱吸附尿素的能力实际上不受2毫摩尔铜和7毫摩尔锌的影响，也不受超生理浓度锂的影响。测定了三根柱的可交换阳离子量，分别为6100、3800和7200毫摩尔。发现阳离子交换剂起到缓冲作用，使整个柱具有0.6摩尔的缓冲能力。在阳离子交换剂层、阴离子交换剂层和活性炭层中，仅发现后者能够结合尿素。
