Share Email Print

Proceedings Paper

Hybrid optical transport trap: loading and unloading of microscale objects using a microfabricated optical fiber into optical tweezers
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

High throughput analysis of trapped samples requires effective loading and unloading into the trap in a microfluidic environment. We demonstrate development of a hybrid optical transport trap (HOTT) which combines a tapered fiberoptic 2D trap for transport of microscopic objects into and out of the optical tweezers trap in an orthogonal geometry. For small cone angle of the tip, the microscopic objects (polystyrene and red blood cells) were found to be trapped in two-dimensions and pushed along the axial direction by domination of scattering force. This was found to be in consistence with the estimated axial forces caused by the beam profiles emerging from the small-cone tapered fiber tip. While for loading of the microscopic objects into the optical tweezers trap, the fiber tip was placed ~ 30μm away from the tweezers trap, unloading was carried out in presence of the tip close (<15 μm) to the tweezers trap. Further, for a fixed fiber trap and tweezers separation (~ 30 μm), both loading and unloading could be achieved by reducing the tweezers trap power so that the scattering force exerted by the fiber trap exceeded the transverse gradient force of tweezers trap. Since the tapered tip can be easily integrated onto a microfluidic channel, the proposed configuration can find potential applications in lab-on-a-chip devices. We demonstrate analysis of transported microscopic objects using digital holographic microscopy integrated with the HOTT.

Paper Details

Date Published: 16 February 2011
PDF: 9 pages
Proc. SPIE 7950, Complex Light and Optical Forces V, 795008 (16 February 2011);
Show Author Affiliations
Nelson Cardenas, The Univ. of Texas at Arlington (United States)
Yogeshwar N. Mishra, The Univ. of Texas at Arlington (United States)
Cochin Univ. of Science & Technology (India)
Samarendra K. Mohanty, The Univ. of Texas at Arlington (United States)

Published in SPIE Proceedings Vol. 7950:
Complex Light and Optical Forces V
David L. Andrews; Enrique J. Galvez; Jesper Glückstad, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?