超高通透析膜的研究与应用

Research and Application of Ultra-High Flux Dialysis Membrane

摘要:

针对慢性肾脏病的治疗，维持性血液透析已成为延缓患者生命的有效治疗方式。但是，对于终末期肾病（ESKD）患者而言，随着透析龄的增加中大分子毒素（分子量>500 Da）的蓄积会导致患者出现各种相关并发症。因此，亟待开发一种具有中大分子毒素清除能力的中空纤维膜，以能够更好地改进透析膜的性能，提高透析质量，进而提高患者生存率。基于此，制备了一种具有高渗透性和选择性的超高通中空纤维膜，该膜对中大分子毒素(12—45 kDa)能实现较好的溶质清除。借助现有成熟透析器的工艺，利用该膜制备超高通透析器。由于超高通中空纤维膜具有与后稀释血液透析滤过（Hemodiafiltration，HDF）相似的溶质去除性能，其可作为HDF的替代/补充模式用于血液透析（Hemodialysis，HD）治疗方案。研究发现，超高通中空纤维膜表面分布着大小均一的孔，断面呈现海绵状结构。采用溶质截留法，测得膜的孔径为7.01 nm，整体孔径分布呈正态曲线分布。通过筛选系数研究发现，超高通透析器对β₂-MG具有高达1的筛选系数，能够控制白蛋白的丢失在5 g范围以内。利用氮气浓缩方式，将昂贵试剂的浓度控制在检测线可检测的范围内，从而建立体外模拟实验大分子的清除指标，确定大分子毒素α₁-MG的清除指标在30 mL?min^-1（允差±20%），确定YKL-40大分子毒素的清除指标在30 mL?min^-1（允差±30%）。本研究提供了一种具有清除中大分子毒素能力的透析膜，建立的中大分子毒素清除指标对改进透析膜性能具有指导意义。

Abstract:

At present， maintenance hemodialysis has become an effective treatment for delaying the life of patients with chronic kidney disease. However， for patients with end-stage kidney disease（ESKD）， with the increase of dialysis age， the accumulation of medium and large molecule toxins （molecular weight>500 Da） can lead to various related diseases. Therefore， it is urgent to develop a hollow fiber membrane with medium and large molecule toxin clearance ability， which can better improve the performance of dialysis membranes， enhance dialysis quality， and ultimately improve patient survival rates. Based on this， a highly permeable and selective ultra high flux hollow fiber membrane was prepared， which achieved good solute removal ability for medium and large molecule toxins （12—45 kDa）. Utilizing the existing mature dialyzer process， an ultra high flux dialyzer was prepared， which can be used as an alternative to HDF in HD treatment mode because the membrane has similar solute removal performance to post diluted HDF. Research has found that the membrane surface of ultra-high flux dialyzer is distributed with uniformly sized pores， with a sponge like cross-section structure； the pore size was measured to be 7.01 nm using solute retention method， and the overall pore size distribution followed a normal distribution curve. From the study of screening coefficients， the ultra-high flux dialyzer has a screening coefficient of up to 1 for β₂-MG， which can control the loss of albumin within 5 g. Using nitrogen concentration method to control the expensive reagents within the detectable range of the detection line， to establish in vitro simulated experimental macromolecule clearance indexes within30 mL?min^-1 （public errand） for the macromolecular toxin α₁-MG； for YKL-40 macromolecular toxin clearance indexes within 30 mL?min^-1（public errand）. This study provides a dialysis membrane with the ability to remove medium and large molecule toxins， and the established removal indexes for medium and large molecule toxins are of guiding significance for improving the performance of dialysis membranes.