Conformal Bioprinting of Bi-phasic Jammed Bioinks, Independent of Gravity, Orientation, and Curvature

Abstract

Rapid in situ bioprinting on complex, human-scale anatomical surfaces remain a key challenge for clinical translation. Here, we present a gravity-independent, conformal bioprinting strategy using bi-phasic granular bioink and multinozzle printheads capable of adapting to arbitrary surface curvatures. The bioink comprised of jammed gelatin microgels suspended in a fibrinogen matrix exhibits yield-stress behavior to maintain shape fidelity after extrusion while supporting cell viability and proliferation. Two monolithic multinozzle printhead architectures with identical bioink delivery networks were evaluated: (1) a rigid configuration for handheld bioprinting and (2) a soft robotic variant capable of real-time curvature adaptation via pneumatic actuation. Microgravity experiments aboard a parabolic flight confirmed successful bioink deposition under [~]0 g conditions. A ladder-rung microfluidic architecture ensured uniform bioink delivery across printhead nozzles, improving deposition consistency. In situ bioprinting on anatomical facial phantoms confirmed conformal, high-throughput (deposition at 20 mm{middle dot}s-1) deposition of bioink over physiologically relevant curvatures, both with and without cells. Cell-laden constructs retained >85% cell viability post-printing and supported proliferation. This work introduces a scalable bioprinting platform suitable for clinical, remote, and deep-space environments, enabling autonomous tissue fabrication. The curvature-adaptive printhead advances current in situ bioprinting capabilities, facilitating the generation of personalized grafts with complex anatomical geometries.