Composition-tunable hyaluronic acid/zwitterionic hybrid fibrous biointerfaces for programmable CD44-mediated cell...

Engineering cell-material interactions on fibrous biointerfaces under flow is crucial for label-free cell handling, yet strong specific adhesion often compromises gentle recovery, often necessitating enzymatic digestion or cleavable chemistries. Here, we developed a composition-tunable electrospun hybrid fibrous biointerface that modulates CD44-hyaluronic acid (HA) adhesion by fiber-level ligand presentation without altering HA chemistry. Methacrylated HA (HAMA) fibers and polycaprolactone (PCL) fibers containing the zwitterionic monomer N-(3-sulfopropyl)-N-(methacryloxyethyl)-N,N-dimethylammonium betaine (SMDB) were co-electrospun and photopolymerized to form composite mats with adjustable HAMA-to-PCL/pSMDB ratios. Increasing HAMA content strengthened CD44-mediated adhesion, whereas higher PCL/pSMDB fractions reduced effective HA density while minimizing nonspecific attachment. The mats were integrated into a custom flow channel, where mixed A549 (CD44⁺) and NIH-3T3 (CD44⁻) suspensions underwent a two-step protocol: low-flow washing of non-adherent cells followed by flow-triggered detachment of adherent CD44⁺ cells, enabling recovery without enzymatic or chemical release steps. Flow rate was used as the controllable operating parameter to compare detachment behaviors across fiber compositions. Among formulations, H3S1 provided a favorable balance-retaining A549 cells under low flow yet enabling complete release under elevated flow-achieving ∼92% recovery of CD44⁺ cells with largely preserved membrane integrity and retained re-adhesion/spreading capacity. Together, these results show that compositional engineering can encode an adhesion "window" coupling selective retention with flow-triggered recovery, and the concept is extendable to other receptor-ligand pairs.