Modular soft robotic microdevices for dexterous biomanipulation† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c8lc01200h

• Published in: Lab on a chip 2019-02, Vol.19 (5), p.778-788
• Main Authors: Özkale, Berna, Parreira, Raquel, Bekdemir, Ahmet, Pancaldi, Lucio, Özelçi, Ece, Amadio, Claire, Kaynak, Murat, Stellacci, Francesco, Mooney, David J., Sakar, Mahmut Selman
• Format: Article
• Language: English
• Subjects: Chemistry
• ISSN: 1473-0197; 1473-0189
• DOI: 10.1039/c8lc01200h

We present a methodology for building biologically inspired, soft microelectromechanical systems (MEMS) devices. We present a methodology for building biologically inspired, soft microelectromechanical systems (MEMS) devices. Our strategy combines several advanced techniques including programmable colloidal self-assembly, light-harvesting with plasmonic nanotransducers, and in situ polymerization of compliant hydrogel mechanisms. We synthesize optomechanical microactuators using a template-assisted microfluidic approach in which gold nanorods coated with thermoresponsive poly( N -isopropylmethacrylamide) (pNIPMAM) polymer function as nanoscale building blocks. The resulting microactuators exhibit mechanical properties (4.8 ± 2.1 kPa stiffness) and performance metrics (relative stroke up to 0.3 and stress up to 10 kPa) that are comparable to that of bioengineered muscular constructs. Near-infrared (NIR) laser illumination provides effective spatiotemporal control over actuation (sub-micron spatial resolution at millisecond temporal resolution). Spatially modulated hydrogel photolithography guided by an experimentally validated finite element-based design methodology allows construction of compliant poly(ethylene glycol) diacrylate (PEGDA) mechanisms around the microactuators. We demonstrate the versatility of our approach by manufacturing a diverse array of microdevices including lever arms, continuum microrobots, and dexterous microgrippers. We present a microscale compression device that is developed for mechanical testing of three-dimensional biological samples such as spheroids under physiological conditions.