Bio-inspired dual-functional phospholipid–poly(acrylic acid) brushes grafted porous poly(vinyl alcohol) beads for selective adsorption of low-density lipoprotein

Abstract

Elevated levels of low-density lipoproteins (LDL) are recognized as a crucial indicator of hyperlipidemia (HLP) and lowering of LDL levels represents an effective clinical treatment strategy. Inspired by the conjugation of phospholipid monolayers and the lipid content of the LDL particle, the current study describes the preparation of an innovative hemoperfusion adsorbent. The adsorbent was prepared by attachment of phosphatidyl ethanolamine to poly(acrylic acid) modified poly(vinyl alcohol-co-triallyl isocyanurate) beads (PVA@PAA–PE). The interaction between LDL and adsorbent mimics the lipoprotein microemulsion present in the blood and thus promotes efficient binding with high affinity. In vitro adsorption using serum from patients with HLP revealed that the LDL adsorption of PVA@PAA–PE was 4.44 times higher than that of controls and the removal rate of LDL using PVA@PAA–PE was about twice as high as that of the anti-atherogenic high-density lipoprotein (HDL). In vivo whole blood perfusion demonstrated the superior affinity of PVA@PAA–PE for LDL since LDL concentration was significantly reduced from 10.71 ± 2.36 mmol L⁻¹ to 6.21 ± 1.45 mmol L⁻¹, while the HDL level was not severely reduced (from 0.98 ± 0.12 mmol L⁻¹ to 0.56 ± 0.15 mmol L⁻¹). Additionally, PVA@PAA–PE exhibited excellent hemocompatibility and low cytotoxicity. Therefore, PVA@PAA–PE is a potential adsorbent for whole blood perfusion to treat hyperlipidemia.