Measuring Wettability of Biosurfaces at the Microscale

  • Conrado AparicioEmail author
  • Yassine Maazouz
  • Dehua Yang
Part of the Methods in Molecular Biology book series (MIMB, volume 811)


Determining the contact angle of a liquid on a solid surface is a simple method to assess the surface wettability. The most common method to measure the contact angle of a liquid consists of capturing the profile of a sessile drop of a few microliters on the surface using an optical system. Currently, this is a widely used technique to analyze wettability both in researched materials and in products of multiple technological fields. However, the drop dispensed by a traditional macroscopic contact angle meter is too big to assess the wettability properties of individual topographical features and/or chemical patterns at the micro/nanoscale. Recently, contact angle meters that can discharge drops that are microscopic, with volumes in the range of 1 × 10−3 to 10−5 μL have been developed. The novel microscopic contact angle meter uses a pneumatic injection system to discharge the drop of the liquid through a capillary of a few micrometers of internal diameter and a high-resolution ultrafast digital camera.

We have tested different biosurfaces – microimprinted polymers for biosensors, calcium-phosphate cements with different topographical microfeatures, orthodontic wires – and assessed the potential applicability in the field in comparison with the conventional macroscopic contact angle meters.

This protocol describes the basic tasks needed to test wettability on biosurfaces with a microscopic contact angle meter. The focus of the protocol is on the challenging methodological steps and those that differentiate the use of this equipment to the use of a traditional macroscopic contact angle meter.

Key words

Microscopic contact angle Wettability Biosurface Biomaterial 


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Department of Restorative Sciences, Minnesota Dental Research Center for Biomaterials and Biomechanics (MDRCBB), School of DentistryUniversity of MinnesotaMinneapolisUSA
  2. 2.Biomaterials, Biomechanics, and Tissue Engineering Research GrroupTechnical University of Catalonia, ETSEIBBarcelonaSpain
  3. 3.EbatcoEden PrairieUSA

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