Rosenbloom Alan J, Sipe David M, Weedn Victor W
Carnegie Mellon University, Molecular Biosensors and Imaging Center (MBIC), 4400 Fifth Avenue, MI292A, Pittsburgh, PA 15213, USA.
J Neurosci Methods. 2005 Oct 30;148(2):147-53. doi: 10.1016/j.jneumeth.2005.04.018. Epub 2005 Jul 25.
Unlike all other currently available sampling techniques, microdialysis allows the continuous recovery of dialysed fluid from the interstitial space of living tissue. Microdialysis has been extensively used to study small molecules such as neurotransmitters, metabolites and drugs in the brain and other tissues. There has been increasing interest in measuring proteins using microdialysis. Optimizing protein recovery requires slow buffer flow rates, large pore membranes and osmotic balancing. An examination of a widely used commercially available large pore (100kDa MWCO) polymeric microdialysis probe, the CMA/20 (polyethersulfone) over 6 days of continuous microdialysis showed that: (1) published molecular weight cut-off values may not predict the size of proteins that can be recovered. This membrane had an effective molecular weight cut-off values (MWCO) of about 29kDa, (2) protein recoveries decrease over time, (3) small proteins are much less affected than larger ones and (4) there can be significant differences in the recovery of proteins similar in size perhaps due to reaching of a critical size, protein aggregation, shape, surface charge or hydrophobicity.
与目前所有其他可用的采样技术不同，微透析能够从活组织的间质空间持续回收透析液。微透析已被广泛用于研究大脑和其他组织中的小分子，如神经递质、代谢物和药物。人们对使用微透析测量蛋白质的兴趣与日俱增。优化蛋白质回收率需要缓慢的缓冲液流速、大孔径膜和渗透平衡。对一种广泛使用的市售大孔径（100kDa分子量截留值）聚合物微透析探针CMA/20（聚醚砜）进行连续6天的微透析研究发现：（1）已公布的分子量截留值可能无法预测能够回收的蛋白质大小。这种膜的有效分子量截留值（MWCO）约为29kDa，（2）蛋白质回收率随时间下降，（3）小蛋白质受影响比大蛋白质小得多，（4）大小相似的蛋白质回收率可能存在显著差异，这可能是由于达到临界大小、蛋白质聚集、形状、表面电荷或疏水性所致。
