Microfluidic fabrication of hydrogel-fiber-based 3D constructs utilizing liquid rope-coil effect

We report a series of microfluidic fabrication techniques based on liquid rope-coil effect. Ca-alginate micro fiber (diameter ~70 μm) based sub-millimeter sized (such as springs, grooved tubes) or macro sized (such as hollow coils, super-coils) 3D constructs can be fabricated using different experimental setups. These constructs are: 1) featured with circumferentially aligned grooved/fibrous morphologies which are advantageous for mimicking many in-vivo structures; 2) able to both efficiently and hierarchically pack-up hydrogel fibers. Furthermore, the proposed methods are compatible with cell encapsulation techniques, thus providing an option for rapid generation of macro/sub-macro cell encapsulated hierarchical 3D constructs for tissue engineering application.