Self-Folding Thermo-Magnetically Responsive Soft Microgrippers
Top Cited Papers
Open Access
- 28 January 2015
- journal article
- Published by American Chemical Society (ACS) in ACS Applied Materials & Interfaces
- Vol. 7 (5), 3398-3405
- https://doi.org/10.1021/am508621s
Abstract
Hydrogels such as poly(N-isopropylacrylamide-co-acrylic acid) (pNIPAM-AAc) can be photopatterned to create a wide range of actuatable and self-folding microstructures. Mechanical motion is derived from the large and reversible swelling response of this cross-linked hydrogel in varying thermal or pH environments. This action is facilitated by their network structure and capacity for large strain. However, due to the low modulus of such hydrogels, they have limited gripping ability of relevance to surgical excision or robotic tasks such as pick-and-place. Using experiments and modeling, we design, fabricate, and characterize photopatterned, self-folding functional microgrippers that combine a swellable, photo-cross-linked pNIPAM-AAc soft-hydrogel with a nonswellable and stiff segmented polymer (polypropylene fumarate, PPF). We also show that we can embed iron oxide (Fe2O3) nanoparticles into the porous hydrogel layer, allowing the microgrippers to be responsive and remotely guided using magnetic fields. Using finite element models, we investigate the influence of the thickness and the modulus of both the hydrogel and stiff polymer layers on the self-folding characteristics of the microgrippers. Finally, we illustrate operation and functionality of these polymeric microgrippers for soft robotic and surgical applications.Keywords
Funding Information
- NIH Office of the Director (DP2-OD004346-01)
- National Institute of Dental and Craniofacial Research (R01 DE013740)
- National Institute of Biomedical Imaging and Bioengineering (R01EB017742)
- National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01 AR0614606)
- Division of Chemical, Bioengineering, Environmental, and Transport Systems (CBET-1066898)
This publication has 49 references indexed in Scilit:
- Rolled-up magnetic microdrillers: towards remotely controlled minimally invasive surgeryNanoscale, 2012
- Microchemomechanical SystemsAdvanced Functional Materials, 2011
- The influence of stereolithographic scaffold architecture and composition on osteogenic signal expression with rat bone marrow stromal cellsBiomaterials, 2011
- Soft Robotics for ChemistsAngewandte Chemie, 2011
- Emerging applications of stimuli-responsive polymer materialsNature Materials, 2010
- Synthesis of poly(propylene fumarate)Nature Protocols, 2009
- Point by Point Comparison of Two Thermosensitive Polymers Exhibiting a Similar LCST: Is the Age of Poly(NIPAM) Over?Journal of the American Chemical Society, 2006
- Organic‐Dye‐Coupled Magnetic Nanoparticles Encaged Inside Thermoresponsive PNIPAM MicrocapsulesSmall, 2005
- A polymeric microgripper with integrated thermal actuatorsJournal of Micromechanics and Microengineering, 2004
- Use of stereolithography to manufacture critical‐sized 3D biodegradable scaffolds for bone ingrowthJournal of Biomedical Materials Research Part B: Applied Biomaterials, 2002