Adsorption and separation of HCV particles by novel affinity aptamer-functionalized adsorbents

•The study prepared novel aptamer-based immunoadsorbents targeting HCV.•Adsorbents covalently immobilized with aptamers were characterized by FTIR and SEM.•Affinity capacity and removal time-point optimization was verified by qPCR and nPCR-NAH.•The novel adsorbents possess good biocompatibility and favorable selectivity.

A novel type of aptamer-functionalized immunoadsorbent was prepared and characterized to remove HCV particles, a promising option of extracorporeal immunoadsorption (ECI) therapy against HCV. Herein, we fabricated a HCV-specific immunoadsorbent where single-stranded DNA aptamers reported and studied previously, modified with amino group at the 5′ terminus, was immobilized covalently onto surfaces of carboxylated-derivative sepharose 4FF beads through N-hydroxysuccinimide (NHS) linkage. Then the adsorbents was evaluated and characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Subsequently, we also confirmed that proposed immunoadsorbents exhibited a favorable biocompatibility as well as specificity. In addition, time-dependent effects of the eradication capacity of aptamer functionalized sepharose beads against HCV was investigated. With the optimized time point, the decontamination performance of HCV particles was assessed by real-time quantitative PCR (qPCR) followed by nucleic acid-based hybridization (NAH), which shows sorbents with an aptamer density of 2 nmol ligand/ml resin could remove approximately 80% (i.e. 8.9 × 106 HCV particles/ml resin) of the HCV genotype 2a cultivated in vitro and 75% (vary with the intial concentration of HCV from about 7.5 × 104–4.4 × 105 HCV particles/ml resin) of the HCV samples from human plasma samples. All these results indicated that the novel aptamer-based adsorbents could effectively remove HCV particles and likely serve as a novel therapy option or at least supplementary for the treatment regimen of HCV.