Advanced gentamicin-loaded chitosan/hydroxyapatite/mesoporous SiO2 scaffold: a comprehensive investigation of drug delivery and cellular interactions

Official URL: https://dx.doi.org/10.1016/j.ijbiomac.2026.151064

Implant-related infections associated with bone implants are a common problem, and traditional antibiotic treatments may cause side effects before the infection at the implant site is cleared. This study aims to develop a biocompatible and biodegradable scaffold that supports bone regeneration while providing localized and controlled antibiotic delivery. Chitosan/hydroxyapatite (CSHA) scaffolds reinforced with mesoporous SiO2 particles were fabricated via freeze-drying. All scaffolds exhibited interconnected pores, with pore sizes of approximately 340 μm in pure chitosan scaffolds, which decreased to around 90 μm in CSHA scaffolds containing mesoporous SiO2 particles. Adding mesoporous SiO2 particles to CSHA scaffolds improved structural strength, increasing the compressive strength from 3.8 ± 0.7 MPa to 22.1 ± 0.8 MPa. The water absorption ratio decreased from 3.9 ± 0.04 to 0.3 ± 0.07, and the 14-day degradation rate dropped from 32% to 20.8%. CSHA scaffolds containing mesoporous particles maintained cell viability above 98% after 7 days and released gentamicin in a controlled manner, with drug-release kinetics best described by the Weibull model. Antimicrobial tests showed strong antibacterial activity in the reinforced scaffolds against Escherichia coli. Overall, CSHA scaffolds with mesoporous SiO2 particles offer a promising option for bone tissue engineering and infection control at the implantation site.