{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T02:12:10Z","timestamp":1789697530915,"version":"4.0.1"},"reference-count":116,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,4,23]],"date-time":"2020-04-23T00:00:00Z","timestamp":1587600000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>With the advent of small-scale robotics, several exciting new applications like Targeted Drug Delivery, single cell manipulation and so forth, are being discussed. However, some challenges remain to be overcome before any such technology becomes medically usable; among which propulsion and biocompatibility are the main challenges. Propulsion at micro-scale where the Reynolds number is very low is difficult. To overcome this, nature has developed flagella which have evolved over millions of years to work as a micromotor. Among the microscopic cells that exhibit this mode of propulsion, sperm cells are considered to be fast paced. Here, we give a brief review of the state-of-the-art of Spermbots\u2014a new class of microrobots created by coupling sperm cells to mechanical loads. Spermbots utilize the flagellar movement of the sperm cells for propulsion and as such do not require any toxic fuel in their environment. They are also naturally biocompatible and show considerable speed of motion thereby giving us an option to overcome the two challenges of propulsion and biocompatibility. The coupling mechanisms of physical load to the sperm cells are discussed along with the advantages and challenges associated with the spermbot. A few most promising applications of spermbots are also discussed in detail. A brief discussion of the future outlook of this extremely promising category of microrobots is given at the end.<\/jats:p>","DOI":"10.3390\/mi11040448","type":"journal-article","created":{"date-parts":[[2020,4,24]],"date-time":"2020-04-24T11:42:14Z","timestamp":1587728534000},"page":"448","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":108,"title":["Sperm Cell Driven Microrobots\u2014Emerging Opportunities and Challenges for Biologically Inspired Robotic Design"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9875-7727","authenticated-orcid":false,"given":"Ajay","family":"Singh","sequence":"first","affiliation":[{"name":"Physical Intelligence Department, Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany"},{"name":"Department of Chemical and Product Safety, German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad","family":"Ansari","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, Via Rinaldo Piaggio 34, 56025 Pontedera, Italy"},{"name":"Department of Excellence in Robotics &amp; AI, Scuola Superiore Sant\u2019Anna, Via Rinaldo Piaggio 34, 56025 Pontedera, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mihir","family":"Mahajan","sequence":"additional","affiliation":[{"name":"K\u00f6nigin-Olga-Stift Gymnasium, Johannesstra\u00dfe 18, 70176 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shubhangi","family":"Srivastava","sequence":"additional","affiliation":[{"name":"Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi 221005, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shubham","family":"Kashyap","sequence":"additional","affiliation":[{"name":"Dr. A.P.J. Abdul Kalam Technical University, Lucknow 226031, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prajjwal","family":"Dwivedi","sequence":"additional","affiliation":[{"name":"Department of Physics, Shri Ramswaroop Memorial University, Lucknow 226007, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vaibhav","family":"Pandit","sequence":"additional","affiliation":[{"name":"Dynex Technologies, 14340 Sullyfield Circle, Chantilly, VA 20151-1621 USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uma","family":"Katha","sequence":"additional","affiliation":[{"name":"BioPharma Division, GALAB Laboratories GmbH, 21029 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"829","DOI":"10.1016\/j.matdes.2011.01.061","article-title":"Bio-inspired approaches to design smart fabrics","volume":"36","author":"Singh","year":"2012","journal-title":"Mater. 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