%0 Journal Article
%T Optoelectrofluidic Manipulation of Nanoparticles and Biomolecules
%A Hyundoo Hwang
%A Je-Kyun Park
%J Advances in OptoElectronics
%D 2011
%I Hindawi Publishing Corporation
%R 10.1155/2011/482483
%X This paper presents optoelectrofluidic technologies for manipulation of nanoparticles and biomolecules. Optoelectrofluidics provides an elegant scheme for the programmable manipulation of particles or fluids in microenvironments based on optically induced electrokinetics. Recent progress on the optoelectrofluidic manipulation of nanoobjects, which include nanospheres, nanowires, nanotubes, and biomolecules, is introduced. Some potential applications of the optoelectrofluidic nanoparticle manipulation, such as nanoparticles separation, nanostructures manufacturing, molecular physics, and clinical diagnostics, and their future directions are also discussed. 1. Introduction A number of advances in micro- and nanomanipulation techniques have been made due to the increase of needs for high performance manipulation¡ªtrapping, transportation, separation, concentration, and assembly¡ªof micro-/nanoobjects in a variety of applications. In particular, manipulating nanoobjects such as nanospheres, nanowires, and biomolecules has provided tremendous opportunities in various application fields, including from device manufacturing to chemical analysis. For addressing such nanoparticle applications, numerous techniques based on various forces such as mechanical [1¨C4], optical [5¨C9], electrical [10¨C13], and magnetic [14, 15] forces have been introduced. In this paper, we present the fundamentals of optoelectrofluidics and the major experiments performed to date for manipulating nanoparticles and molecules using the optoelectrofluidic platforms. Recent progress and some potential applications of optoelectrofluidic technology for nanoparticle manipulation, as well as its future direction are discussed. 2. Conventional Techniques for Nanoparticle Manipulation: Optical and Electrical Methods Optical manipulation techniques have attracted much attention for a long time since the appearance of optical tweezers in 1970 [5] and been one of the most frequently used methods because one can directly trap and transport individual particles on demand based on the optical field of a tightly focused laser beam. However, it is well known that a lower bound on the size to which light can be focused is limited by the diffraction limit, which is given by ., where and . are the wavelength of the light and the numerical aperture of the lens, respectively [16]. Despite such limitations, conventional optical tweezers have been used to trap not only viruses [17] and biological cells [18] but also metallic nanoparticles [6], nanowires [7], and carbon nanotubes (CNTs) [8]. When the target object
%U http://www.hindawi.com/journals/aoe/2011/482483/