Bioprinted nanoparticles for tissue engineering applications.

Tissue engineering may require precise patterning and monitoring of cells and bioactive factors within the scaffold. We investigated a new hybrid nanobioprinting technique that facilitates manipulation and tracking of cells and bioactive factors within a three-dimensional tissue construct. This technique combines the initial patterning capabilities of syringe-based cell deposition with the active patterning capabilities of superparamagnetic nanoparticles. Superparamagnetic iron oxide nanoparticles, either in the alginate biopolymer or loaded inside endothelial cells, were bioprinted using a solid freeform fabrication direct cell writing system. Bioprinting did not impact cell viability when nanoparticles were in the alginate. However, both control and printed samples with 0.1 or 1.0 mg/mL nanoparticles in the alginate showed a 16% or 35% viability loss at 36 h after printing, respectively. Nanoparticle loading in cells decreased cell viability to 11% and bioprinting decreased viability to an additional 29...