Advances in conductive microneedles: From fabrications to applications

Abstract

Conductive microneedles (CMNs) combine the minimally invasive characteristics of microneedles with the electrical functionality required for sensing, recording, stimulation, and controlled drug delivery. By penetrating the stratum corneum with reduced pain and tissue damage, they provide efficient access to the skin microenvironment and have shown strong potential in wearable healthcare, precision diagnostics, and intelligent therapeutics. Despite these advantages, challenges remain in balancing mechanical robustness with electrical functionality, improving fabrication precision and reproducibility, maintaining interfacial stability, and achieving scalable manufacturing. In this review, the major fabrication routes for CMNs are summarized and compared in terms of forming principles, material compatibility, and conductivity-introduction strategies. Secondly, research on the key performances of CMNs is discussed. After that, the applications of CMNs in electrochemical sensing, bioelectrical signal acquisition, electrostimulation therapy, and drug delivery are overviewed, followed by a brief discussion of current challenges and future perspectives.

Keywords

Conductive microneedles / transdermal device / fabrication strategies / electrochemical sensing / bioelectrical recording / drug delivery

Acknowledgements

ChatGPT (OpenAI, GPT-5.5) was used solely for language editing and polishing of the manuscript. The authors take full responsibility for the integrity, accuracy, and originality of the content.

Authors contribution

Zhang QT: Supervision, writing-review & editing. Zhang Q: Writing-original draft. Tang SY: Conceptualization, writing-review & editing. Wu L, Gaira S, Lai J, Wang R, Zhao Y: Writing-review & editing.

Conflicts of interest

The authors declare no conflicts of interest.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent for publication

Not applicable.

Availability of data and materials

Not applicable.

Funding

The work was funded by the Australian Research Council Future Fellowship (Grant No. FT230100257), Discovery Project (Grant No. DP250103029), and UNSW Scientia Fellowship (This program does not have a grant number).

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