Protocol for developing shape-morphing 4D bioprinted magnetic constructs to promote articular cartilage regeneration using silk fibroin-gelatin bioink

External magnetic fields can regulate cellular responses. Here, we present a protocol to fabricate magnetic constructs by 4D bioprinting with shape-morphing properties using silk fibroin-gelatin bioinks for articular cartilage regeneration. We illustrate the steps for magnetic bioink formulation, bioprinting, and chondrogenic induction of human bone marrow mesenchymal stem/stromal cells. We detail the steps to actuate the constructs using an external magnetic field and then characterize chondrogenesis. Magnetic field actuation may be helpful for mechanically activating constructs for articular cartilage regeneration. For complete details on the use and execution of this protocol, please refer to Chakraborty et al.¹.