From cells to organs: Technical challenges of two-photon polymerization in biomedical engineering

Abstract

Nanomanufacturing technology is crucial in advancing sophisticated biomedical devices, biochips, tissue engineering, and advanced biomedical materials. Two-photon polymerization (TPP) offers nanoscale fabrication precision, eliminates the need for masks, and allows the creation of arbitrary three-dimensional structures, providing technical advantages unparalleled by traditional methods. Applying TPP technology in the biomedical field presents new challenges related to materials and systems. Although there has been significant discussion regarding biomaterials, comparatively little attention has been given to the limitations of manufacturing systems for biomedical functional devices. Commercial TPP systems predominantly rely on point-by-point scanning for fabrication, which leads to low throughput. From a biomedical perspective, the goal is to achieve manufacturing precision at the single-cell level while scaling production throughput to the organ level. Advancements in precision and throughput are critical to expanding the applications of TPP in biomedical engineering. This review introduces the fundamental principles of TPP and summarizes recent advancements in TPP applications within tissue engineering, medical devices, and microfluidics. It then delves into the technological progress of TPP in recent years, focusing on aspects such as system design, manufacturing processes, and fabrication principles. The review highlights advancements in areas including the kinetics of light–matter interactions and the development of cutting-edge techniques such as spatiotemporal focusing. Finally, it discusses future development directions of TPP technology in biomedical applications

Keywords

Biomedical functional devices / Kinetics / Spatiotemporal focusing / Tissue engineering / Two-photon polymerization

Funding

This study was funded National Natural Science Foundation of China (92477111, 22073003), Beijing Natural Science Foundation (L232109), Fundamental Research Funds for the Central Universities (YWF-22-K101).

Conflict of Interest

Jiebo Li is a Guest Editor of this special issue, but was not in any way involved in the editorial and peer-review process conducted for this paper, directly or indirectly. Separately, other authors declared that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper.

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