20.500.12556/DKUM-98889 3D printed curcuminoid-loaded nanocellulose–alginate scaffolds with tunable mechanical and diffusion-controlled release properties This study reports the fabrication of curcuminoid-loaded nanofibrillated cellulose (NFC)– alginate scaffolds via extrusion-based 3D printing, integrating supercritical CO2 extraction with biofabrication. NFC–alginate inks were pre-crosslinked with CaCl2 (1 to 10 mM) to tune structure and properties. Rheological analysis confirmed shear-thinning behavior suitable for extrusion printing. Mechanical testing revealed a non-linear dependence on crosslinking: optimal performance was achieved by Ink 2 (1 mM CaCl2 with curcuminoid extract), with tensile strength increasing from ~0.60 to ~0.80 MPa and Young’s modulus from ~1.5 to ~3.0 MPa relative (Ink 1, 10 mM CaCl2, without extract), reflecting the combined effect of extract incorporation and ionic pre-crosslinking rather than crosslinker concentration alone; higher crosslinking reduced stiffness (~1.15 MPa). SEM revealed porous architectures (Ink 1: 542 ± 63 μm; Ink 4: 398 ± 71 μm) with increasing structural heterogeneity upon curcuminoid incorporation. In vitro release exhibited biphasic, diffusion-dominated behavior, reaching ~50 to 60% in ethanol-containing media; PBS inclusion as a physiological reference confirmed minimal release (<5%), consistent with the known hydrophobicity and pH-dependent instability of curcuminoids and defining the physicochemical delivery boundaries of the system. The highest release (~372 ng/mL) was achieved at intermediate loading (10×). Kinetic modeling confirmed Higuchi-type diffusion as the dominant mechanism (R2 ≈ 0.90 to 0.99). These results establish a clear structure–property–release relationship and position the scaffolds as a tunable, diffusioncontrolled delivery platform for hydrophobic bioactives in topical or formulation-assisted applications employing co-solvents or solubilizing excipients. nanocellulose alginate curcumin extract supercritical-CO2 ionic-crosslinking kinetic release and mechanical properties 3D-printing nanoceluloza alginati ekstrakt kurkumina superkritični ogljikov dioksid antioksidanti antimikrobne značilnosti ionsko zamreženje 3D tiskanje mehanske lastnosti true false true MDPI Angleški jezik Slovenski jezik https://www.mdpi.com/journal/polysaccharides Članek v reviji 2026-07-15 09:11:29 2026-07-15 09:11:31 2026-07-21 13:29:23 0000-00-00 00:00:00 2026 0 0 25 str. št. 3, št. članka 84 Letn. 7 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 2026-04-21 2026-07-07 2026-07-11 66 284703491 10.3390/polysaccharides7030084 2673-4176 polysaccharides-07-00084.pdf polysaccharides-07-00084.pdf 1 86ED9D7A44CC389A0AD8E8FC41574932 a7c066c93bad804dc761c11c826637e15417894f08430906118b1195833913ad 49452856-801d-11f1-8699-00155d580e34 https://dk.um.si/Dokument.php?lang=slv&id=208281 https://www.mdpi.com/2673-4176/7/3/84 0 6bf3b344-84f7-11f1-9f9e-00155d580e34 https://dk.um.si/Dokument.php?lang=slv&id=208463 Fakulteta za kemijo in kemijsko tehnologijo Medicinska fakulteta Fakulteta za elektrotehniko, računalništvo in informatiko 0 0 0