The microparticulate inks for bioprinting applications

Three-dimensional (3D) bioprinting has emerged as a groundbreaking technology for fabricating intricate and functional tissue constructs. Central to this technology are the bioinks, which provide structural support and mimic the extracellular environment, which is crucial for cellular executive function. This review summarizes the latest developments in microparticulate inks for 3D bioprinting and presents their inherent challenges. We categorize micro-particulate materials, including polymeric microparticles, tissue-derived microparticles, and bioactive inorganic microparticles, and introduce the microparticle ink formulations, including granular microparticles inks consisting of densely packed microparticles and composite microparticle inks comprising microparticles and interstitial matrix. The formulations of these microparticle inks are also delved into highlighting their capabilities as modular entities in 3D bioprinting. Finally, existing challenges and prospective research trajectories for advancing the design of microparticle inks for bioprinting are discussed.