3D-printed ceramic scaffolds with colloidal silver and Moringa oleifera extracts for potential antimicrobial water...

Ceramic filters are an effective, low-cost solution for water potabilization, particularly in rural communities. The integration of 3D printing has advanced this traditional approach by enabling precise control over design parameters that govern filtration efficiency. Gyroid-type ceramic scaffolds for water treatment were fabricated by clay-based extrusion 3D printing. Two ceramic pastes (ECP 1 and ECP 2) containing kaolin, attapulgite, alumina, and feldspar were formulated; ECP 2 incorporated 10 wt% activated carbon as a sacrificial porogenic phase. Rheological characterization using rotational rheometry and Bingham model fitting identified 40 wt% water as optimal for extrusion. Sintering at 1100°C produced interconnected open-pore networks in ECP 2 (apparent porosity: 23.6%; water absorption: 11.8%). Scaffolds were functionalized with silver nanoparticles (AgNPs) and ethanolic extracts of Moringa oleifera. AgNPs exhibited surface plasmon resonance at 422 nm; silver leaching was 0.00282 ppm (WHO limit: 0.1 ppm). Ethanolic extract E2 (80% v/v) showed significantly lower MIC (0.175 g/mL) than E1 (0.35 g/mL; p < 0.05) and bactericidal activity (MBC/MIC ⩽ 4.0). Functionalized scaffolds (EG) reduced biofilm formation by 80%-95% versus controls at 24 h (MTT assay) and maintained cellular compatibility above the 80% ISO 10993-5 threshold at 7 days. This combination of properties positions them as a highly promising alternative for advanced ceramic water filters.