Immobilizing argatroban and mPEG-NH₂ on a polyethersulfone membrane surface to prepare an effective nonthrombogenic biointerface

Systemic anticoagulation is not suitable for hemodialysis (HD) patients with a high risk of bleeding in the clinic. An HD membrane that provides a localized anticoagulation membrane surface may be a promising strategy to solve this intractable problem for HD patients. Herein, we modified a nonthrombogenic polyethersulfone (PES) dialyzer membrane by grafting argatroban (AG) and methoxy polyethylene glycol amine (mPEG-NH2) via a polydopamine (PDA) strategy. The PES substrates were immersed in an alkaline dopamine solution for 24 h, and then, AG and mPEG-NH2 were sequentially grafted covalently onto the resultant membrane. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) were utilized to confirm the successful introduction of PDA and the immobilization of AG and mPEG-NH2. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to observe the surface structure and morphology after the surface modification. The excellent antithrombotic abilities of the modified membrane were demonstrated by the suppression of platelet adhesion and activation, prolongation of clotting times, and inhibition of thrombin generation and complement activation. This work describes an efficient and convenient method to immobilize AG and mPEG-NH2 to create a nonthrombogenic biointerface for blood-contacting devices such as HD membranes.