Cellular studies and sustained drug delivery via nanostructures fabricated on 3D printed porous Neovius lattices of Ti₆Al₄V ELI

Abstract

Site-specific drug delivery has the potential to reduce drug dosage by 3 to 5-folds. Given the propensity of drugs used in the treatment of tuberculosis and cancers, the increased drug dosages via oral ingestion for several months to a few years of medication is often detrimental to the health of patients. In this study, the sustained delivery of drugs with multiscale structured novel Neovius lattices was achieved. 3D Neovius Open Cell Lattices (NOCL) with porosities of 40, 45, and 50 % were fabricated layer-by-layer on the laser bed fusion process. Micron-sized Ti6Al4V Eli powder was used for 3D printing. The Young’s modulus achieved from the novel Neovius lattices were in the range of 1.2 to 1.6 GPa, which is comparable to human cortical bone and helps to improve implant failure due to the stress shielding effect. To provide sustained drug delivery, nanotubes (NTs) were fabricated on NOCLs via high-voltage anodisation. The osteogenic agent icariin was loaded onto the NOCL-NT samples and their release profiles were studied for 7 days. A significantly steady and slow release rate of 0.05% per hour of the drug was achieved using NOCL-NT. In addition, the initial burst release of NOCL-NT was 4 fold lower than that of the open-cell lattices without nanotubes. Cellular studies using MG63 human osteoblast-like cells were performed to determine their biocompatibility and osteogenesis which were analysed using Calcein AM staining and Alamar Blue after 1, 5, and 7 days. 3D printed NOCL samples with NTs and with Icariin loaded NTs demonstrated a significant increase in cell proliferation as compared to as printed NOCL samples.

Orthopedic Scaffolds: Evaluation of Structural Strength and Permeability of Fluid Flow via an Open Cell Neovius Structure for Bone Tissue Engineering

“…About 20 000 MG63 human osteoblast-like cells (ATCC) were drop-seeded onto the scaffolds, and the cells were allowed to adhere for 1 h before a 1.5 mL growth medium was added to each well. After 1, 3, 5, and 7 days of culture, the cell viability was assessed by Alamar blue assay similar to our previous study …”

“…After 1, 3, 5, and 7 days of culture, the cell viability was assessed by Alamar blue assay similar to our previous study. 31 Briefly, the viability index using Alamar blue assay was calculated based on the measured absorbance values using a microplate reader (Thermofisher Scientific Multiskan SkyHigh Microplate Spectrophotometer) with emission/excitation wavelengths of 570 and 600 nm. The viability index (difference between samples and control) is given by 3.2.…”