By Topic

Microoptical characterization and modeling of positioning forces on drosophila embryos self-assembled in two-dimensional arrays

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

6 Author(s)
Xiaojing Zhang ; Dept. of Biomed. Eng., Univ. of Texas, Austin, TX, USA ; Chung-Chu Chen ; Bernstein, R.W. ; Zappe, S.
more authors

In this paper, we describe high-precision experimental and numerical characterization of the positioning forces acting on Drosophila embryos that have self-assembled onto 2-D arrays of hydrophobic sites on a silicon substrate in water. The forces measured using a surface micromachined optical-encoder force sensor operating in reflection, are in good agreement with numerical simulations based on an extended surface energy model for the oil-based fluidic system. The positioning forces of ellipsoidal embryos on flat sites show a linear-spring-like relationship between the force and displacement on rectangular as well as cross-shaped sites. An average detachment force of 8.9 μN±1.3 μN was found for the immobilized embryos on 250 μm×100 μm sites. The cross-shaped site has only 19.85% of the area of the rectangular site, but provides a comparable positioning force with a significant reduction in embryo clustering. In contrast, the positioning forces of flat silicon chips, similar in size to the embryos, are linear in the displacement only over a limited range (0∼40 μm), and are then constant up to the detachment force (25.0 μN±3.5 μN). Our measurements also show significant hysteresis in the force vs. displacement, indicating that variations in the surface properties play an important role in the self-assembly process.

Published in:

Microelectromechanical Systems, Journal of  (Volume:14 ,  Issue: 5 )