In-vitro assessment of β-tricalcium phosphate/bredigite-ciprofloxacin (CPFX) scaffolds for bone treatment applications

In the present study, beta-tricalcium phosphate (beta-TCP) scaffolds with various amounts of bredigite (Bre) were fabricated by the space holder method. The effect of bredigite content on the structure, mechanical properties, in vitro bioactivity, and cell viability was investigated. The structural assessment of the composite scaffolds presented interconnected pores with diameter of 300-500 mu m with around 78%-82% porosity. The results indicated that the compressive strength of the scaffolds with 20% bredigite (1.91 MPa) was improved in comparison with scaffolds with 10% bredigite (0.52 MPa), due to the reduction of the average pore and grain sizes. Also, the results showed that the bioactivity and biodegradability of beta-TCP/20Bre were better than that of beta-TCP/10Bre. Besides, in this study, the release kinetics of ciprofloxacin (CPFX) loaded beta-TCP/Bre composites as well as the ability of scaffolds to function as a sustained release drug carrier was investigated. Drug release pattern of beta-TCP/bredigite-5CPFX scaffolds exhibited the rapid burst release of 43% for 3 h along with sustained release (82%) for 32 h which is favorable for bone infection treatment. Antibacterial tests revealed that the antibacterial properties of beta-TCP/bredigite scaffolds are strongly related to the CPFX concentration, wherein the scaffold containing 5% CPFX showed the most significant zone of inhibition (33 +/- 0.5 mm) against Staphylococcus aureus. The higher specific surface areas of nanostructure beta-TCP/bredigite scaffolds containing CPFX lead to an initial rapid release followed by constant drug delivery. MTT assay showed that the cell viability of beta-TCP/bredigite scaffold loading with up to 1%-3% CPFX (95 +/- 2%), is greater than for scaffolds containing 5% CPFX (84 +/- 2%). In Overall, it may suggested that beta-TCP/bredigite containing 1%-3% CPFX possesses great cell viability and antibacterial activity and be employed as bactericidal biomaterials and bone infection treatment.

Automated summary

This study investigated the impact of bredigite content on the structure, mechanical properties, in vitro bioactivity, and cell viability of beta-tricalcium phosphate (beta-TCP) scaffolds. Results showed that scaffolds with 20% bredigite exhibited improved compressive strength and better bioactivity compared to scaffolds with 10% bredigite. Additionally, the release kinetics of ciprofloxacin (CPFX) loaded beta-TCP/bredigite composites and antibacterial properties were studied, indicating that scaffolds containing 1%-3% CPFX had higher cell viability and antibacterial activity, making them potential candidates for bone infection treatment.