Researchers at the University of Illinois at Urbana-Champaign have developed a new flow-based method for manipulating and confining single particles in free solution, a process that will help address current challenges faced by nanoscientists and engineers.

Today, fine-scale manipulation of small particles remains a major challenge in the field. Current methods for particle trapping mainly rely on electrokinetic, magnetic, or optical force fields, which may not be compatible with biomolecules or biological systems.

Together, Schroeder and Tanyeri developed a “microfluidic trap” capable of 2-D particle manipulation using the sole action of fluid flow.

Schroeder and researchers demonstrate several unique features of the microfluidic trap, including 2-D manipulation of particles as small as 500 nanometers in size in water, with a positioning precision of only about 180 nanometers, trapping of particles as small as 100 nanometers, and active control over the solution conditions of a trapped particle. All of this is achieved with a simple PDMS-based microfluidic device without the need for complex instrumentation for optical trapping or electric field generation.

“The microfluidic trap provides a fundamentally new method for the trapping and analysis of single particles or single molecules, complementing existing techniques,” Schroeder said. “Our new technology will find pervasive use in interdisciplinary fields such as nanoscience, materials science, complex fluids, soft materials, microbiology, and molecular biology.”

Schroeder and Tanyeri said they now have the ability to trap a range of particle sizes.

“Unlike existing methods such as conventional optical or magnetic traps, the microfluidic trap will allow for trapping of tiny nanoparticles, less than 30 nanometers in free solution,” Tanyeri said.

With the precise positional control of single nanoparticles in free solution, scientists will be able to explore new technologies, from molecular engineering to bottom-up assembly of nanostructures.

This story is reprinted from material from University of Illinois, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.