Precision hydrogel environments for advanced microbial culture and patterning

Abstract

Hydrogel materials and scaffolds have emerged as transformative tools in biological research by offering precise control over cell viability, metabolism, and productivity. Their compatibility with three-dimensional (3D) bioprinting and patterning technologies enables the precise and reproducible organization of living components, facilitating novel experimental paradigms across diverse disciplines. Although most 3D hydrogel research has emphasized mammalian cell applications, particularly in tissue engineering, there is a growing body of research applying these technologies to study, manipulate, and harness a variety of microorganisms, such as bacteria. This review explores the latest advances in microbial hydrogel encapsulation, focusing on material selection and patterning methods designed to preserve microbial viability and function. We compare the distinct requirements and challenges of culturing microorganisms in hydrogels versus mammalian systems and highlight recent breakthroughs in bacterial bioprinting that are advancing microbiological research, paving the way for current and emerging applications in various areas, including oral health. By synthesizing current knowledge and identifying promising future directions, this review underscores the potential of microbial hydrogel culture as a versatile platform for investigating microbial communities, probing bacterial– material interactions, and engineering living materials with applications in human health and environmental systems.

Keywords

Bacteria–material interaction / Bacterial bioprinting / Microbial hydrogel culture / Microbial living materials / Three-dimensional bioprinting

Funding

This work was funded by the National Institute of Dental and Craniofacial Research (Nos. R01DE029479A and DE029479S). Financial support was also provided through the ADA Forsyth Institute (Grant No. AFISU105).

Conflict of Interest

The authors declare they have no competing interests.

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