Design and characterization of a dual-network silicone/β-CD-HA hydrogel for controlled drug delivery

Silicone hydrogels have emerged as promising candidates for ocular drug delivery due to their exceptional oxygen permeability. However, their inherent hydrophobicity often results in suboptimal drug-loading capacity and patient discomfort. To address these limitations, this study introduces an innovative dual-network silicone/β-CD-HA hydrogel. In this design, the primary silicone network preserves high oxygen permeability, while the secondary β-CD-HA network enhances hydrophilicity and introduces additional drug-loading sites via host-guest interactions. Levofloxacin (LVF), a broad-spectrum antibiotic, was incorporated into the hydrogel through non-covalent binding with β-CD, and the system’s drug-loading capacity, sustained release profile, in vitro bactericidal activity, and post-loading properties were systematically evaluated. The results demonstrated a total LVF loading of 959.90 ± 36.60 μg/lens in the silicone/β-CD-HA hydrogel, with sustained release extending up to 8 h. Bactericidal assays revealed markedly reduced E. coli survival rates in treated groups: 14.46 ± 0.76 % (p < 0.0001) for LVF-loaded silicone hydrogel and 10.42 ± 1.66 % (p < 0.0001) for the β-CD-HA/silicone hydrogel, underscoring the enhanced antimicrobial efficacy of the dual-network system. The integration of β-CD-HA significantly improved hydrogel hydrophilicity, increasing equilibrium water content (EWC) from 27.69 ± 0.18 % to 45.60 ± 0.19 % and reducing the surface contact angle from 99.41 ± 0.24° to 70.36 ± 0.14°. Crucially, the modified hydrogel retained functionality-critical properties, exhibiting 93.45 ± 0.42 % light transmittance and 110.45 ± 0.32 barrer oxygen permeability values well within practical application standards. Post-drug-loading characterization showed minimal changes in oxygen permeability (105.47 ± 0.18 barrer), transmittance, or mechanical integrity, confirming structural stability. These findings collectively highlight the dual-network silicone/β-CD-HA hydrogel as a robust platform for extended ocular drug delivery, effectively balancing enhanced drug loading, sustained release kinetics, without compromising essential material properties. • Levofloxacin loading in silicone/β-CD-HA hydrogel was 959.90±36.60 μg/lens, with sustained release for up to 8 h. • β-CD-HA integration enhanced hydrogel hydrophilicity, elevating EWC to 45.60±0.19% and lowering the contact angle to 70.36±0.14°. • The oxygen permeability of the drug-loaded silicone/β-CD-HA hydrogel was 105.47±0.18 barrer, with little change in transmittance and mechanical properties.