Polymer Microfibers: Fabrication, Structural Design, Functionalization, and Biomedical Applications

Microfibers are rapidly emerging as versatile building blocks for next-generation biomedical devices due to their precisely tunable morphology, chemistry, and functionality. However, most existing reviews primarily focus on electrospun nanofibers or broadly discuss nanofiber systems, where the focus on microfiber areas is limited. Herein, this review presents a comprehensive and systematic roadmap for the design and fabrication of microfibers tailored for healthcare applications. We first survey state-of-the-art fabrication technologies emphasizing their respective capabilities in controlling fiber diameter, alignment, internal architecture, and production throughput. We then discuss material selection strategies encompassing natural, synthetic, and hybrid composite systems. Subsequently, we examine key structural motifs, and elucidate how architectural design governs mass transport, cell-fiber interactions, and spatiotemporally controlled therapeutic release. We further outline functionalization strategies that transform passive microfibers into smart platforms. Finally, we highlight representative biomedical applications with high translational potential and commercial microfiber-based products. We conclude by discussing current translational challenges and future perspectives. Thus, this review provides practical design principles and strategic insights to accelerate the development and clinical translation of microfiber-based biomedical technologies.