Interactive light-powered lab-on-a-chip: simultaneous actuation of microstructures by optical manipulation

Abstract

We demonstrate the flexibility of a multiple-beam trapping system that enables interactive manipulation of fluid-borne colloidal structures with advanced controllability and versatility that can lead to light-powered microdevices performing multiple functions in a 'lab-on-a-chip'. A straightforward phase-imaging operation forms the basis for the efficient generation of arbitrarily shaped trapping beam configurations. The multiple-beam trapping pattern is a direct map of the phase variation encoded on a programmable phase-only spatial light modulator (SLM). A graphical user interface that encodes desired phase patterns onto the SLM enables interactive and independent control over the dynamics and geometry of each trapping beam. Experimental results show that the system can be used for guided assembly of particles in a plane, control of particle stacking along a beam axis, and real-time sorting of inhomogeneous mixtures of microspheres. These experiments illustrate that multiple beams generated by the system can be utilized not only for the improved synthesis of functional microstructures but also for their non-contact and parallel actuation crucial for sophisticated microfluidic-based lab-on-a-chip demonstrations in the future.

Dielectric microsphere manipulation and chain assembly by counter-propagating waves in a channel waveguide

“…These systems would normally incorporate particle trapping and sorting. These functions can be accomplished by various methods [1], including optical methods [2,3]. Optical trapping by means of a tightly focused laser beam has already proven to be a valuable research tool for biomanipulation [4].…”

A Next Generation BioPhotonics Workstation

“…Miniaturization has also become a trend in fields such as biology and medicine. So called lab-on-a-chip devices [3,4], for example, integrate experimental measurement, sample handling and other functionalities on a chip that can be mounted on a microscope. Aside from taking up less space, smaller setups require less power to operate, less raw materials, and tend to be more efficient in transporting electrons, photons or even cells, as shorter distances are traversed unlike in typical wires, fibers or tubes.…”

Sorting of polystyrene microspheres using a Y-branched optical waveguide

“…Recently, optical methods have been proposed to control microfluidic processes and achieve particle sorting. A multiple-beam trapping system has been proposed for powering active microfluidic components produced either by microfabrication or by colloidal formation [8]. Using a dynamically reconfigurable optical lattice MacDonald et.…”