Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > No compromises: JILA's short, flexible, reusable AFM probe

This image shows JILA's modified AFM probes measuring DNA molecules. The older mod (long cantilever, right) eliminated the usual gold coating to enhance long-term stability. The latest version (left) retains the gold coating where needed to reflect light but maintains excellent stability. Researchers also removed a large section to reduce stiffness and friction near surfaces. The new probe provides precise results much faster than before, while reducing "noise" (colored squiggles).

Credit: Credit: Baxley/JILA
This image shows JILA's modified AFM probes measuring DNA molecules. The older mod (long cantilever, right) eliminated the usual gold coating to enhance long-term stability. The latest version (left) retains the gold coating where needed to reflect light but maintains excellent stability. Researchers also removed a large section to reduce stiffness and friction near surfaces. The new probe provides precise results much faster than before, while reducing "noise" (colored squiggles).

Credit: Credit: Baxley/JILA

Abstract:
JILA researchers have engineered a short, flexible, reusable probe for the atomic force microscope (AFM) that enables state-of-the-art precision and stability in picoscale force measurements. Shorter, softer and more agile than standard and recently enhanced AFM probes, the JILA tips will benefit nanotechnology and studies of folding and stretching in biomolecules such as proteins and DNA.

No compromises: JILA's short, flexible, reusable AFM probe

Posted on April 9th, 2014

An AFM probe is a cantilever, shaped like a tiny diving board with a small, atomic-scale point on the free end. To measure forces at the molecular scale in a liquid, the probe attaches its tip to a molecule such as a protein and pulls; the resulting deflection of the cantilever is measured. The forces are in the realm of piconewtons, or trillionths of a newton. One newton is roughly the weight of a small apple.

The new probe design, described in ACS Nano,* is the JILA research group's third recent advance in AFM technology. JILA is jointly operated by the National Institute of Standards and Technology (NIST) and University of Colorado Boulder.

The group previously improved AFM position stability by using laser beams to sense motion** and removing the gold coating from long probe tips, or cantilevers, to enhance long-term force stability.*** However, removing the gold reduces the strength of the signal being measured, and using long cantilevers leads to other measurement problems such as slower response to dynamic events like protein unfolding.

The latest modification overcomes these and other issues, improving precision without loss of stability, speed, or sensitivity. JILA researchers used a focused ion beam to cut a hole in the center of a short commercial cantilever and thinned the remaining support structures, thereby reducing the cantilever's stiffness and friction near surfaces. The result is excellent long-term stability and improved short-term precision, respectively, in AFM force measurements.

JILA researchers also added a protective glass cap over the gold coating at the end of the cantilever to retain beneficial reflectivity, and then removed the remaining gold to gain force stability. The modified cantilever enables rapid, precise and stable force measurements across a broad range of operating frequencies.

"Previously, we had to average the Brownian (random) motion of our favorite cantilever for about 60 milliseconds to get a measurement that had a precision of 1 piconewton," JILA/NIST biophysicist Tom Perkins says. "Now, we can get the same precision in 1 millisecond or so."

JILA researchers demonstrated significant benefits for single molecule studies. For instance, the short, soft cantilevers can quickly measure abrupt changes in force when a protein unfolds. Protein folding is required for proper biological function and misfolding can lead to diseases such as Alzheimer's. The new cantilevers match the response of stiffer, unmodified cantilevers but with greater stability and precision. Force stability is crucial in this application because protein folding and unfolding rates are exponentially sensitive to tiny changes (smaller than 1 piconewton) in applied load. The new device also can track fleeting nanoscale events, including protein folding, over hundreds of seconds—much longer periods than previously possible. The new design should also be applicable to rapid probing of the mechanical properties of materials at the nanoscale.

Significantly, the new cantilevers are robust enough to be reused for multiple days. Moreover, JILA researchers say the new design is simple and inexpensive to make, and thus, suitable for routine use.

"Amazingly, this project was spearheaded by a talented undergraduate. We hope other groups with similarly talented students will adopt these cantilevers. We certainly are," Perkins said.

###

The research was supported by the National Science Foundation and NIST.

*M.S. Bull, R.M.A. Sullan, H. Li and T.T. Perkins. Improved single-molecule force spectroscopy using micromachined cantilevers. ACS Nano. Published online March 26,2014. DOI:10.1021/nn5010588

####

For more information, please click here

Contacts:
Laura Ost

303-497-4880

Copyright © National Institute of Standards and Technology (NIST)

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

**See 2009 NIST Tech Beat article, "Making a Point: Picoscale Stability in a Room-Temperature AFM," at:

***See 2012 NIST Tech Beat article "Not-So-Precious: Stripping Gold From AFM Probes Allows Better Measurement of Picoscale Forces,"at:

Related News Press

News and information

GLOBALFOUNDRIES and Chengdu Partner to Expand FD-SOI Ecosystem in China: More than $100M investment to establish a center of excellence for FDXTM FD-SOI design May 23rd, 2017

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Leti Will Demo World’s-first WVGA 10-µm Pitch GaN Microdisplays for Augmented Reality Video at Display Week in Los Angles: Invited Paper also Will Present Leti’s Success with New Augmented Reality Technology That Reduces Pixel Pitch to Less than 5 Microns May 22nd, 2017

Graphene-nanotube hybrid boosts lithium metal batteries: Rice University prototypes store 3 times the energy of lithium-ion batteries May 19th, 2017

Laboratories

NREL’s Advanced Atomic Layer Deposition Enables Lithium-Ion Battery Technology: May 10th, 2017

Discovery of new transparent thin film material could improve electronics and solar cells: Conductivity is highest-ever for thin film oxide semiconductor material May 6th, 2017

Sandia develops math techniques to improve computational efficiency in quantum chemistry May 5th, 2017

Scientists Set Record Resolution for Drawing at the One-Nanometer Length Scale: An electron microscope-based lithography system for patterning materials at sizes as small as a single nanometer could be used to create and study materials with new properties May 1st, 2017

Govt.-Legislation/Regulation/Funding/Policy

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Graphene-nanotube hybrid boosts lithium metal batteries: Rice University prototypes store 3 times the energy of lithium-ion batteries May 19th, 2017

Stanford scientists use nanotechnology to boost the performance of key industrial catalyst May 18th, 2017

Oddball enzyme provides easy path to synthetic biomaterials May 17th, 2017

Discoveries

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Sensors detect disease markers in breath May 19th, 2017

Graphene-nanotube hybrid boosts lithium metal batteries: Rice University prototypes store 3 times the energy of lithium-ion batteries May 19th, 2017

Plasmon-powered upconversion nanocrystals for enhanced bioimaging and polarized emission: Plasmonic gold nanorods brighten lanthanide-doped upconversion superdots for improved multiphoton bioimaging contrast and enable polarization-selective nonlinear emissions for novel nanoscal May 19th, 2017

Announcements

GLOBALFOUNDRIES and Chengdu Partner to Expand FD-SOI Ecosystem in China: More than $100M investment to establish a center of excellence for FDXTM FD-SOI design May 23rd, 2017

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Leti Will Demo World’s-first WVGA 10-µm Pitch GaN Microdisplays for Augmented Reality Video at Display Week in Los Angles: Invited Paper also Will Present Leti’s Success with New Augmented Reality Technology That Reduces Pixel Pitch to Less than 5 Microns May 22nd, 2017

Graphene-nanotube hybrid boosts lithium metal batteries: Rice University prototypes store 3 times the energy of lithium-ion batteries May 19th, 2017

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Sensors detect disease markers in breath May 19th, 2017

Graphene-nanotube hybrid boosts lithium metal batteries: Rice University prototypes store 3 times the energy of lithium-ion batteries May 19th, 2017

Plasmon-powered upconversion nanocrystals for enhanced bioimaging and polarized emission: Plasmonic gold nanorods brighten lanthanide-doped upconversion superdots for improved multiphoton bioimaging contrast and enable polarization-selective nonlinear emissions for novel nanoscal May 19th, 2017

Tools

Plasmon-powered upconversion nanocrystals for enhanced bioimaging and polarized emission: Plasmonic gold nanorods brighten lanthanide-doped upconversion superdots for improved multiphoton bioimaging contrast and enable polarization-selective nonlinear emissions for novel nanoscal May 19th, 2017

The brighter side of twisted polymers: Conjugated polymers designed with a twist produce tiny, brightly fluorescent particles with broad applications May 16th, 2017

Racyics Launches ‘makeChip’ Design Service Platform for GLOBALFOUNDRIES’ 22FDX® Technology: Racyics will provide IP and design services as a part of the foundry’s FDXcelerator™ Partner Program May 11th, 2017

UnitySC Announces Wafer Thinning Inspection System; Win from Power Semiconductor IDM for Automotive: Leading IDM Selects New 4See Series Automated Defect Inspection Platform for Power Semiconductor Automotive Applications May 11th, 2017

Nanobiotechnology

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Sensors detect disease markers in breath May 19th, 2017

Oddball enzyme provides easy path to synthetic biomaterials May 17th, 2017

The brighter side of twisted polymers: Conjugated polymers designed with a twist produce tiny, brightly fluorescent particles with broad applications May 16th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project