The realization of a permanent surface hydrophilization for highly porous microparticles designed for removing uremic toxins from the blood of renal failure patients, without altering their complex pore structure, represents a challenging task.

Here we report on the hydrophilic surface functionalization of porous poly (ether imide) (PEI) microparticles, having a mean diameter of 226 ± 14 μm, a porosity of around 84 ± 2% with a mean pore diameter of 230 ± 40 nm, by covalent attachment of amino-terminated poly (vinyl pyrrolidone) (PVP–NH₂) with a number average molecular weight of M_n = 5400 g mol⁻¹. X-ray photoelectron spectroscopy confirmed a successful surface modification by a change in the surface chemistry, in particular the N/C ratio. The PEI-PVP particles exhibited an advancing water contact angle of θ_adv = 75° ± 5° as determined in environmental scanning electron microscopy microwetting experiments. The obtained results from mercury intrusion porosimetry and nitrogen adsorption experiments documented the preservation of the porous structure of the particles in the cause of the modification, which could be visualized by electron microscopy. The presented approach enables a covalent hydrophilization of porous particles while preserving their nanoporous morphology.

实现高度多孔的微粒的永久表面亲水化的目的是从肾衰竭患者的血液中去除尿毒症毒素，而不改变其复杂的孔结构，这是一项艰巨的任务。

在这里我们报告了多孔聚醚醚酰亚胺（PEI）微粒的亲水性表面官能化，其平均直径为226±14μm，孔隙率约为84±2％，平均孔径为230±40 nm。数均分子量为M _n  = 5400 g mol ^-1的氨基末端聚（乙烯基吡咯烷酮）（PVP-NH ₂）的共价连接。X射线光电子能谱证实通过改变表面化学，特别是N / C比，成功地进行了表面改性。的PEI-PVP的颗粒表现出的水前进接触角θ_进阶 在环境扫描电子显微镜微湿实验中确定为= 75°±5°。从压汞法和氮吸附实验获得的结果表明，改性后颗粒的多孔结构得以保留，这可以通过电子显微镜观察。提出的方法能够使多孔颗粒共价亲水化，同时保留其纳米孔形态。