Twardowski Z J, Nolph K D, McGary T J, Moore H L
Am J Hosp Pharm. 1983 Apr;40(4):583-6.
The influence of temperature and time on insulin adsorption to plastic peritoneal dialysis bags was evaluated. A dialysis bag (1.5% dextrose, 2 liters) was injected with 25-microCi insulin I 125 and gently mixed. This bag was then attached to another empty bag of the same type. Following a bag-to-bag transfer method, the amount of insulin adsorbed on the plastic bags was measured at 24 degrees C and 37 degrees C, and after a 12-hour warming period at 37 degrees C. Regular insulin was added to the system in 40-unit increments up to 280 units. Radioactivity in all of the samples was measured in a gamma counter. As the amount of regular insulin increased, the percentage of insulin adsorbed decreased at both temperatures. More insulin was bound at 37 degrees C than at 24 degrees C for all levels of insulin. Data calculated according to the Langmuir isotherm equation showed that the maximum possible values of adsorption to the system at 24 degrees C and 37 degrees C were 17.8 and 18.4 units, respectively. The affinity constants at 24 degrees C and 37 degrees C were 0.0039 and 0.0065, respectively. The influence of prolonged warming at 37 degrees C was minimal. At the usual dosage of insulin (below 40 units) prescribed to the majority of dialysis patients, less than 9% (3.5 units) is adsorbed onto the dialysis bags.
评估了温度和时间对胰岛素吸附于塑料腹膜透析袋的影响。向一个透析袋（含1.5%葡萄糖，2升）中注入25微居里的胰岛素I 125并轻轻混匀。然后将此袋连接到另一个相同类型的空袋上。采用袋间转移法，在24℃和37℃以及在37℃温育12小时后，测量吸附在塑料袋上的胰岛素量。以40单位的增量向系统中添加正规胰岛素，直至280单位。所有样品中的放射性在γ计数器中测量。随着正规胰岛素量的增加，在两个温度下胰岛素的吸附百分比均下降。对于所有胰岛素水平，37℃时结合的胰岛素比24℃时更多。根据朗缪尔等温方程计算的数据表明，在24℃和37℃时系统的最大可能吸附值分别为17.8和18.4单位。24℃和37℃时的亲和常数分别为0.0039和0.0065。37℃长时间温育的影响最小。在大多数透析患者规定的常规胰岛素剂量（低于40单位）下，吸附到透析袋上的胰岛素不到9%（3.5单位）。
