Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > New Constant Diameter NeedleProbes™ with Unique Ability to Measure Liquid Surface Properties by AFM

Abstract:
Constant diameter NeedleProbes™ for Atomic Force Microscopy (AFM) have been developed and are opening up a new area of research for studies at the liquid/air interface. The NeedleProbes' cylindrical geometry enables researchers to measure surface tension, contact angle, meniscus height, evaporation rate and viscosity - all in a single force distance curve.

New Constant Diameter NeedleProbes™ with Unique Ability to Measure Liquid Surface Properties by AFM

Phoenix, AZ | Posted on December 15th, 2009

New, constant diameter NeedleProbes are enabling unique measurements at the liquid/air interface. These NeedleProbes' cylindrical geometry enables a new area of research for liquid studies. "AFM can now be used to measure surface tension, contact angle, meniscus height, evaporation rate and viscosity - all in a single force distance curve" says Mehdi Yazdanpanah, inventor of the NeedleProbes. The new metallic probes have recently been introduced for a variety of applications, many of which had been impractical for AFM.

Atomic force microscopy routinely takes advantage of force-distance curves to measure interactions between an AFM tip and a sample surface. An example would be extending the tip to a liquid surface so the wetting force can be measured. Although standard probes can detect wetting force, surface tension and contact angle are very complicated to determine. Imprecise knowledge of the length of contact and angle of the meniscus with the sides of the tip make such measurements impractical using standard AFM probes. Furthermore, with increasing insertion depth, the attractive force of standard tips continues to grow as the contact line increases. The large force can eventually overcome the cantilever and result in the unintended immersion of the cantilever into the liquid.

The NeedleProbes' differentiating feature is the cylindrical shape, in contrast to the pyramidal or conical shape of most standard AFM probes. With the NeedleProbes, the liquid's attractive force is constant as the tip is immersed. When a NeedleProbe has a second region with a larger diameter, there is a step change in force when this larger region enters the liquid. The figure shows a diagram that differentiates between a conventional probe and a NeedleProbe entering a liquid medium.

The surface tensions for several low molecular weight liquids were measured with the NeedleProbes. Results were between -4.2 % and +8.3 % of standard reported values. Also, the F-D curves showed well-defined stair-step events on insertion and retraction from partial wetting liquids, compared to conventional AFM probes. A NeedleProbe with a step change in diameter at a known distance from its end produced two steps in the F-D curve from which the meniscus height was determined. The step features enable meniscus height to be determined from distance between the steps, as an alternative to calculating the height corresponding to the AFM measured values of surface tension and contact angle.

####

About Nanoscience Instruments
Nanoscience Instruments provides solutions to scientists, engineers, and educators around the world. Our products and services serve the fast growing field of nanoscience, with a focus on scanning probe microscopy and nanoscale surface analysis instrumentation.

For more information, please click here

Contacts:
www.nanoscience.com/contact/

Copyright © PRWeb

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 News Press

News and information

Iranians Present Model to Predict Photocatalytic Process in Removal of Pollutants October 30th, 2014

Production of Biocompatible Polymers in Iran October 30th, 2014

Amorphous Coordination Polymer Particles as alternative to classical nanoplatforms for nanomedicine October 30th, 2014

Nanosafety research – there’s room for improvement October 29th, 2014

Announcements

Iranians Present Model to Predict Photocatalytic Process in Removal of Pollutants October 30th, 2014

Production of Biocompatible Polymers in Iran October 30th, 2014

Amorphous Coordination Polymer Particles as alternative to classical nanoplatforms for nanomedicine October 30th, 2014

Nanosafety research – there’s room for improvement October 29th, 2014

Tools

A new cheap and efficient method to improve SERS, an ultra-sensitive chemical detection technique October 28th, 2014

New Compact SIMS at 61st AVS | Visit us on Booth 311 October 28th, 2014

New nanodevice to improve cancer treatment monitoring October 27th, 2014

Haydale Secures Exclusive Development and Supply Agreement with Tantec A/S: New reactors to be built and commissioned by Tantec A/S represent another step forward towards the commercialisation of graphene October 24th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE