Résumé
Electrospun poly(ϵ-caprolactone) (PCL)nanobrous mats are widely considered for blood-contacting wound dressings and small-diameter vascular applications; however, their intrinsic hydrophobicity limits rapid wetting and controlled interaction with blood. In this work, we modulate the interfacial response of PCL nanobers by incorporating oxideshelled silicon nanoparticles (SiNPs) synthesized by pulsed laser ablation in liquid, a ligand-free approach that avoids organic stabilizers and preserves surface reactivity. Two composite architectures were designed: SiNPs embedded within the ber bulk (PAC-1, -4, -16) and SiNPs preferentially exposed at the ber surface (SPAC-1, -4, -16), with systematically increasing nanoparticle loadings. Structural characterization conrmed the retention of a homogeneous brous morphology and the targeted nanoparticle distribution. The dynamic interaction with whole blood was quantied using time-resolved contact-angle measurements, complemented by top-view optical microscopy and three-dimensional prolometry of dried droplets. Pristine PCL remained strongly hydrophobic, exhibiting a high apparent contact angle that decreased only marginally over time (≈110° to ≈100° over 20 min), whereas a hydrophilic PCL functionalized with APTES showed rapid spreading. Incorporation of SiNPs within the ber volume led to only a moderate enhancement of wettability (final angles ≈80-90°), and dried droplets retained compact morphologies with limited spreading. In contrast, surface-decorated mats displayed a sharp, concentration-dependent transition toward highly wettable behavior: for SPAC-16, the contact angle fell below 20°, droplet proles became markedly attened, and microscopy revealed extended plasma-rich regions surrounding a red-cell-rich core, indicative of pronounced phase separation within the nanobrous network. Consistently, gravimetric measurements showed substantial increases in both water uptake (from ≈400% for PCL to > 700% for SPAC-16) and blood uptake (up to ≈1200% for PAC-16 and ≈1050% for SPAC-16).Overall, these results establish laser-synthesized SiNPs as an effective and chemically simple strategy to control blood wetting, imbibition, and phase separation in electrospun PCL nanofibers. Importantly, nanoparticle localization - within the fiber bulk or at the fiber surface - governs distinct regimes of interfacial behavior. This work provides mechanistic insight into early blood-material interactions on nanofibrous substrates and offers clear design guidelines for tailoring fluid management and hemocompatibility in advanced wound dressing and blood-contacting biomaterials.