Title
Optical manipulation of single magnetic beads in a microwell array on a digital microfluidic chip Optical manipulation of single magnetic beads in a microwell array on a digital microfluidic chip
Author
Faculty/Department
Faculty of Applied Economics
Publication type
article
Publication
Washington, D.C. ,
Subject
Chemistry
Engineering sciences. Technology
Source (journal)
Analytical chemistry. - Washington, D.C.
Volume/pages
88(2016) :17 , p. 8596-8603
ISSN
0003-2700
ISI
000382805900037
Carrier
E
Target language
English (eng)
Full text (Publishers DOI)
Affiliation
University of Antwerp
Abstract
The detection of single molecules in magnetic microbead microwell array formats revolutionized the development of digital bioassays. However, retrieval of individual magnetic beads from these arrays has not been realized until now despite having great potential for studying captured targets at the individual level. In this paper, optical tweezers were implemented on a digital microfluidic platform for accurate manipulation of single magnetic beads seeded in a microwell array. Successful optical trapping of magnetic beads was found to be dependent on Brownian motion of the beads, suggesting a 99% chance of trapping a vibrating bead. A tailor-made experimental design was used to screen the effect of bead type, ionic buffer strength, surfactant type, and concentration on the Brownian activity of beads in microwells. With the optimal conditions, the manipulation of magnetic beads was demonstrated by their trapping, retrieving, transporting, and repositioning to a desired microwell on the array. The presented platform combines the strengths of digital microfluidics, digital bioassays, and optical tweezers, resulting in a powerful dynamic microwell array system for single molecule and single cell studies.
Handle