Skip to main content
  • Submit
  • About
    • Editorial Board
    • PNAS Staff
    • FAQ
    • Accessibility Statement
    • Rights and Permissions
    • Site Map
  • Contact
  • Journal Club
  • Subscribe
    • Subscription Rates
    • Subscriptions FAQ
    • Open Access
    • Recommend PNAS to Your Librarian
  • Log in
  • My Cart

Main menu

  • Home
  • Articles
    • Current
    • Special Feature Articles - Most Recent
    • Special Features
    • Colloquia
    • Collected Articles
    • PNAS Classics
    • List of Issues
  • Front Matter
  • News
    • For the Press
    • This Week In PNAS
    • PNAS in the News
  • Podcasts
  • Authors
    • Information for Authors
    • Editorial and Journal Policies
    • Submission Procedures
    • Fees and Licenses
  • Submit
  • About
    • Editorial Board
    • PNAS Staff
    • FAQ
    • Accessibility Statement
    • Rights and Permissions
    • Site Map
  • Contact
  • Journal Club
  • Subscribe
    • Subscription Rates
    • Subscriptions FAQ
    • Open Access
    • Recommend PNAS to Your Librarian

User menu

  • Log in
  • My Cart

Search

  • Advanced search
Home
Home

Advanced Search

  • Home
  • Articles
    • Current
    • Special Feature Articles - Most Recent
    • Special Features
    • Colloquia
    • Collected Articles
    • PNAS Classics
    • List of Issues
  • Front Matter
  • News
    • For the Press
    • This Week In PNAS
    • PNAS in the News
  • Podcasts
  • Authors
    • Information for Authors
    • Editorial and Journal Policies
    • Submission Procedures
    • Fees and Licenses

New Research In

Physical Sciences

Featured Portals

  • Physics
  • Chemistry
  • Sustainability Science

Articles by Topic

  • Applied Mathematics
  • Applied Physical Sciences
  • Astronomy
  • Computer Sciences
  • Earth, Atmospheric, and Planetary Sciences
  • Engineering
  • Environmental Sciences
  • Mathematics
  • Statistics

Social Sciences

Featured Portals

  • Anthropology
  • Sustainability Science

Articles by Topic

  • Economic Sciences
  • Environmental Sciences
  • Political Sciences
  • Psychological and Cognitive Sciences
  • Social Sciences

Biological Sciences

Featured Portals

  • Sustainability Science

Articles by Topic

  • Agricultural Sciences
  • Anthropology
  • Applied Biological Sciences
  • Biochemistry
  • Biophysics and Computational Biology
  • Cell Biology
  • Developmental Biology
  • Ecology
  • Environmental Sciences
  • Evolution
  • Genetics
  • Immunology and Inflammation
  • Medical Sciences
  • Microbiology
  • Neuroscience
  • Pharmacology
  • Physiology
  • Plant Biology
  • Population Biology
  • Psychological and Cognitive Sciences
  • Sustainability Science
  • Systems Biology
Research Article

Tetherless thermobiochemically actuated microgrippers

Timothy G. Leong, Christina L. Randall, Bryan R. Benson, Noy Bassik, George M. Stern, and David H. Gracias
PNAS January 20, 2009 106 (3) 703-708; https://doi.org/10.1073/pnas.0807698106
Timothy G. Leong
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Christina L. Randall
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Bryan R. Benson
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Noy Bassik
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
George M. Stern
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
David H. Gracias
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • For correspondence: dgracias@jhu.edu
  1. Edited by James R. Heath, California Institute of Technology, Pasadena, CA, and accepted by the Editorial Board November 25, 2008 (received for review August 5, 2008)

Related Article

  • In This Issue
    - Jan 20, 2009
  • Article
  • Figures & SI
  • Info & Metrics
  • PDF
Loading

Article Figures & SI

Figures

  • Fig. 1.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Fig. 1.

    Schematic diagram depicting side and top views of the key steps in the fabrication and operation of the microgripper trilayer joints. (A) The bimetallic joint component (orange and light gray) was evaporated above the sacrificial layer (blue) and silicon (dark gray) substrate. The Cr layer (light gray) developed residual tensile stress during evaporation, denoted by σT. (B) The Ni phalange (green) and the polymer trigger layer (red) were then patterned above the bimetallic layer. (C) The sacrificial layer was dissolved to release the microgripper from the substrate in a planar, open configuration. (D) When heated or exposed to selected chemicals, mechanical property changes in the polymer trigger allowed the stressed bimetallic layer to flex.

  • Fig. 2.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Fig. 2.

    Scanning electron microscope images highlighting variability in rotational symmetry, number of digits and palm shape, and number of joints per digit. (A and B) Closed microgrippers with a rotationally asymmetric (A) and symmetric (B) arrangement of digits around the central palm. Note the gap in gripper A that resulted because of the asymmetry. The Insets depict the layout of the gripper when open. (C–E) Closed grippers with pentagonal (C), hexagonal (D), and heptagonal (E) palms and a symmetric arrangement of digits. (F–H) Closed grippers with 2-jointed digits (F) and 3-jointed digits (G and H). The Insets depict the open configuration of each digit. (G) Empty gripper with 3 digits closed such that the distal phalange is parallel to the proximal phalange. (H) Gripper closed around a bead. When the bead was captured, the distal phalanges could not flex completely and pushed against the bead.

  • Fig. 3.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Fig. 3.

    Dependence of the multilayer joint angle on thin film parameters. Predicted joint angles resulting from a change in polymer elasticity for various Cu thicknesses in the range of 200–250 nm (Cr was kept constant at 50 nm). The joint angles were predicted from a multilayer thin film model (details in SI Text). The theoretical calculation reflects the change in the polymer elastic modulus and the resulting joint angle as the polymer layer of the joint is triggered with heat or chemicals.

  • Fig. 4.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Fig. 4.

    Thermally triggered actuation, magnetic manipulation, and bead capture. (A and B) Optical images of 23 grippers (face-up and face-down) triggered to close en masse by heating. (C) Overlaid movie sequence (Movie S1) showing the remote-controlled manipulation of a mobile gripper in a coiled tube. (D) Schematic diagram depicting remote, magnetically directed movement and capture of a bead on a substrate. (E–I) Optical microscopy sequence showing the remote-controlled, thermally triggered capture of a dyed bead (275 μm) from among several clear beads.

  • Fig. 5.
    • Download figure
    • Open in new tab
    • Download powerpoint
    Fig. 5.

    Thermally and biochemically triggered cell capture. (A–E) Optical microscopy sequence showing the thermally triggered capture and retrieval of Neutral red-stained cells from a cell culture mass at the end of a 1.5-mm-diameter tube (Movie S3). (F) Zoomed detail of the microgripper with the cells captured in A–E demonstrating viability (red). (G) Fluorescent micrograph demonstrating viability of thermally captured LIVE/DEAD stained cells. Note that the photopatternable polymer in the joints fluoresces red under UV excitation. (H) Fluorescent micrograph with viable cells (green) captured by using a thermal trigger and incubated for 72 h afterward. (I) Fluorescent micrograph of viable cells captured by using a biochemical trigger to actuate the gripper. (J) Optical image of a microgripper with captured cells from a sample of a bovine bladder. (K) Overlaid optical micrograph sequence depicting the traversing of a gripper from left to right through an orifice in a bovine bladder tissue sample.

Data supplements

  • Supporting Information

    Files in this Data Supplement:

    • Download Supporting Information (PDF)
    • Download Movie 1 (avi)
    • Download Movie 2 (avi)
    • Download Movie 3 (avi)
PreviousNext
Back to top
Article Alerts
Email Article

Thank you for your interest in spreading the word on PNAS.

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Tetherless thermobiochemically actuated microgrippers
(Your Name) has sent you a message from PNAS
(Your Name) thought you would like to see the PNAS web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Tetherless thermobiochemically actuated microgrippers
Timothy G. Leong, Christina L. Randall, Bryan R. Benson, Noy Bassik, George M. Stern, David H. Gracias
Proceedings of the National Academy of Sciences Jan 2009, 106 (3) 703-708; DOI: 10.1073/pnas.0807698106

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Request Permissions
Share
Tetherless thermobiochemically actuated microgrippers
Timothy G. Leong, Christina L. Randall, Bryan R. Benson, Noy Bassik, George M. Stern, David H. Gracias
Proceedings of the National Academy of Sciences Jan 2009, 106 (3) 703-708; DOI: 10.1073/pnas.0807698106
Digg logo Reddit logo Twitter logo Facebook logo Google logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Mendeley logo Mendeley
Proceedings of the National Academy of Sciences: 106 (3)
Table of Contents

Submit

Sign up for Article Alerts

Article Classifications

  • Physical Sciences
  • Engineering

Jump to section

  • Article
    • Abstract
    • Methods
    • Acknowledgments
    • Footnotes
    • References
  • Figures & SI
  • Info & Metrics
  • PDF

You May Also be Interested in

Abstract depiction of a guitar and musical note
Science & Culture: At the nexus of music and medicine, some see disease treatments
Although the evidence is still limited, a growing body of research suggests music may have beneficial effects for diseases such as Parkinson’s.
Image credit: Shutterstock/agsandrew.
Scientist looking at an electronic tablet
Opinion: Standardizing gene product nomenclature—a call to action
Biomedical communities and journals need to standardize nomenclature of gene products to enhance accuracy in scientific and public communication.
Image credit: Shutterstock/greenbutterfly.
One red and one yellow modeled protein structures
Journal Club: Study reveals evolutionary origins of fold-switching protein
Shapeshifting designs could have wide-ranging pharmaceutical and biomedical applications in coming years.
Image credit: Acacia Dishman/Medical College of Wisconsin.
White and blue bird
Hazards of ozone pollution to birds
Amanda Rodewald, Ivan Rudik, and Catherine Kling talk about the hazards of ozone pollution to birds.
Listen
Past PodcastsSubscribe
Goats standing in a pin
Transplantation of sperm-producing stem cells
CRISPR-Cas9 gene editing can improve the effectiveness of spermatogonial stem cell transplantation in mice and livestock, a study finds.
Image credit: Jon M. Oatley.

Similar Articles

Site Logo
Powered by HighWire
  • Submit Manuscript
  • Twitter
  • Facebook
  • RSS Feeds
  • Email Alerts

Articles

  • Current Issue
  • Latest Articles
  • Archive

PNAS Portals

  • Anthropology
  • Chemistry
  • Classics
  • Front Matter
  • Physics
  • Sustainability Science
  • Teaching Resources

Information

  • Authors
  • Editorial Board
  • Reviewers
  • Librarians
  • Press
  • Site Map
  • PNAS Updates

Feedback    Privacy/Legal

Copyright © 2021 National Academy of Sciences. Online ISSN 1091-6490