Theta Thursday #3 - It's a Small World: Contact Angles at the Picoliter Scale

Welcome back to the Theta Optical Tensiometry Masterclass Series! Session 2 will focus on measuring contact angles on small surfaces.

Liquid contact angle measurements with an optical tensiometer can be a powerful approach to assess adhesion, cleanliness, fluidics, and general material wettability in many fields and applications. These measurements conventionally employ liquid droplets on the microliter scale translating to surface areas of multiple square millimeters.

While our modern dispensers with a high needle gauge tip can consistently dispense down to 100 nL droplets, this still may not be small enough for purposes like printing, medical device tubing, or microelectronics. For these applications, we need to equip the Theta picoliter droplet dispenser, a piezoelectric inkjet dispenser that makes droplets as small as 20 picoliters possible. In this masterclass webinar, we will showcase how to setup up contact angle measurements with the Theta Picoliter dispenser and highlight hardware accessories and software tools for high-quality and consistent measurements.

We will cover:

·         Setting up the picoliter dispenser and optics with the Theta Flex/Flow optical tensiometer.

·         Parameters for capturing accurate and in-focus contact angle images.

·         Using hardware accessories for thin films and small fibers/tubing.

·         Software recipes in OneAttension for consistent droplet recording and data analysis.

About the Theta Thursdays Masterclass Series:

Coming this Fall 2024, Nanoscience Instruments will be hosting a series of Theta Optical Tensiometry demonstration masterclasses. This series will focus on giving pragmatic, hands-on applications of optical tensiometry techniques beyond basic contact angle measurements. While these measurements still have their importance, the Theta Optical tensiometers have many advanced capabilities that may be underutilized. To bridge this gap, each session will focus on a different technique, like tilting or roughness corrected contact angle measurements. This will include helpful tips for the set up and execution of each technique, while avoiding common mistakes for a more successful measurement. We hope this series will inspire current and potential Theta tensiometry users to expand their measurement arsenal and gain the knowledge necessary to apply these techniques confidently.

Session 1: Going Full-Tilt: Dynamic Contact Angle Measurements with a Tilting Cradle – October 10

Session 2: Applying Roughness Corrected Contact Angle with the 3D Topography Module – October 31

Session 3: It’s a Small World: Contact Angles at the Picoliter Scale – November 19

Session 4: Dynamic Contact Angle Measurements with a Tilting Stage – TBD

Session 5: Captive Bubble and Interfacial Tension Measurements w/ Hooked Needle – TBD

Session 6: Dilatational Interfacial Rheology with the Pulsating Drop Module – TBD