{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T11:16:11Z","timestamp":1788434171964,"version":"build-2803163510"},"reference-count":38,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T00:00:00Z","timestamp":1788393600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Special Support Plan of the Guangdong Province","award":["2025TQ09Z574"],"award-info":[{"award-number":["2025TQ09Z574"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Microneedle-based transdermal drug delivery enables painless and efficient drug administration but is limited by insufficient mechanical strength and high insertion forces. Inspired by the efficient penetration capability of cactus spines, this study investigated the microstructure and biomechanics of natural cactus spines and bioinspired microneedles. Finite element analysis showed that a groove width of 50 \u03bcm produced the highest stress and strain. Solid bioinspired microneedles were fabricated by 3D printing, while dissolvable hyaluronic acid, chitosan, and gelatin microneedles were prepared using femtosecond laser-fabricated titanium molds and replica molding. Optimized laser parameters generated micropores approximately 500 \u03bcm deep. Mechanical tests showed insertion forces of 60\u2013100 mN for solid microneedles, with the 50 \u03bcm groove design exhibiting the highest value. Among dissolvable microneedles, gelatin displayed the greatest mechanical strength, whereas hyaluronic acid demonstrated the best overall potential for transdermal drug delivery.<\/jats:p>","DOI":"10.3390\/bios16090488","type":"journal-article","created":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T10:10:33Z","timestamp":1788430233000},"page":"488","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Mechanical Properties and Fabrication of Bioinspired Cactus Spine Microneedles"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-8678-8807","authenticated-orcid":false,"given":"Hongru","family":"Liu","sequence":"first","affiliation":[{"name":"School of Electro-Mechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"State Key Laboratory for High Performance Tools, Guangdong University of Technology, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiang","family":"Long","sequence":"additional","affiliation":[{"name":"School of Electro-Mechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"State Key Laboratory for High Performance Tools, Guangdong University of Technology, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiumeng","family":"Sun","sequence":"additional","affiliation":[{"name":"School of Electro-Mechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"State Key Laboratory for High Performance Tools, Guangdong University of Technology, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shixiong","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Electro-Mechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"State Key Laboratory for High Performance Tools, Guangdong University of Technology, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhishan","family":"Yuan","sequence":"additional","affiliation":[{"name":"School of Electro-Mechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"Guangdong Provincial Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology, Guangdong University of Technology, Guangzhou 510006, China"},{"name":"State Key Laboratory for High Performance Tools, Guangdong University of Technology, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"119673","DOI":"10.1016\/j.ijpharm.2020.119673","article-title":"Current trends in polymer microneedle for transdermal drug delivery","volume":"587","author":"Mahmood","year":"2020","journal-title":"Int. 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