Microvascular network based on the Hilbert curve for nutrient transport in thick tissue.

To address the uneven nutrient distribution within three-dimensional (3D) tissue models and organoids currently used in medical research, this study introduces a microvascular network based on the Hilbert curve. Our aim was to develop innovative solutions for enhancing nutrient supply in thick tissue models in vitro. By using 3D bioprinting, we engineered microvascular networks of varying Hilbert orders and validated their efficacy in enhancing nutrient uniformity through numerical simulations and experiments. These networks facilitated broader and more uniform nutrient distribution throughout the thick tissue models, particularly the 2° Hilbert microvascular structure, which occupies less space and significantly reduces regions of cellular death. Furthermore, we explored the potential of assembling larger tissue constructs using the 2° Hilbert microvascular network, showcasing its applicability in constructing large-scale biological models. The findings suggest that the 2° Hilbert microvascular structure is particularly effective in ensuring adequate nutrient delivery, thus enhancing the viability and functionality of large-volume tissue models. These innovations hold significant promise for advancing the fields of tissue engineering and regenerative medicine by improving nutrient delivery to in vitro thick tissue block models. This provides a robust foundation for future in vitro research and clinical applications, potentially leading to more effective treatments and interventions in the medical field. The development of these microvascular networks represents a crucial step forward in overcoming the limitations of current 3D tissue models and organoids, paving the way for more sophisticated and reliable biomedical research tools.