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Abstract Granular hydrogels composed of hydrogel microparticles are promising candidates for 3D bioprinting due to their ability to protect encapsulated cells. However, to achieve high print fidelity, hydrogel microparticles need to jam to exhibit shear‐thinning characteristics, which is crucial for 3D printing. Unfortunately, this overpacking can significantly impact cell viability, thereby negating the primary advantage of using hydrogel microparticles to shield cells from shear forces. To overcome this challenge, a novel solution: a biphasic, granular colloidal bioink designed to optimize cell viability and printing fidelity is introduced. The biphasic ink consists of cell‐laden polyethylene glycol (PEG) hydrogel microparticles embedded in a continuous gelatin methacryloyl (GelMA)‐nanosilicate colloidal network. Here, it is demonstrated that this biphasic bioink offers outstanding rheological properties, print fidelity, and structural stability. Furthermore, its utility for engineering complex tissues with multiple cell types and heterogeneous microenvironments is demonstrated, by incorporating β‐islet cells into the PEG microparticles and endothelial cells in the GelMA‐nanosilicate colloidal network. Using this approach, it is possible to induce cell patterning, enhance vascularization, and direct cellular function. The proposed biphasic bioink holds significant potential for numerous emerging biomedical applications, including tissue engineering and disease modeling. 

Abstract A series of glucose‐based degradable superabsorbent hydrogels with potential to tackle issues associated with sustainability, flooding, and drought has been designed and fabricated. These hydrophilic networks were constructed through integrating glucose as a primary building block –into cyclic oligomers and block polymers, which were combined into mechanically‐interlocked slide‐ring crosslinked materials. Crosslinking of slide ring α‐cyclodextrin/poly(ethylene glycol)‐type polyrotaxanes with acid‐functionalized ABA triblock copolymers comprised of mercaptopropionic acid‐functionalized poly(glucose carbonate (ethyl propargyl carbonate))‐b‐poly(ethylene glycol)‐b‐mercaptopropionic acid‐functionalized poly(glucose carbonate (ethyl propargyl carbonate)), afforded degradable superabsorbent hydrogels through establishment of chemically‐labile ester linkages, in addition to glycosidic and carbonate groups of the polymer precursors. With an emphasis on development of fundamental synthetic design strategies to achieve high‐performance superabsorbent hydrogels that could behave as robust materials, which are derived from natural components and exhibit hydrolytic degradability, effort went into optimization of the composition, structure, and topology leading to water uptake capacities >30× by mass. Investigations of composition‐structure‐topology‐morphology effects on properties as a function of variations of PEG main chain length, degree of α‐cyclodextrin coverage, and concentration of pre‐gel solution, indicated that the slide‐ring polymer and triblock copolymer networks feature high water uptake, tunable mechanical properties, and sustainability with construction from renewable natural products and in‐built degradability.