School of
Information Technology and Electrical Engineering

Speaker: Mr Gabriel Dumy, ESPCI Paris
Seminar Date: Thu, 07/02/2019 - 11:00
Venue: 49-502; AEB Seminar Room
Host: Dr Mickael Mounaix

Seminar Type: Guest Research Seminar

Abstract: 

Contactless manipulation of micro-objects is currently a very promising area of research, with application ranging from single cell analysis to whole tissue culture. Starting from optical tweezers, these experimental techniques have now been extended to their acoustic counterpart, exploiting either standing acoustic waves, or travelling waves exhibiting a helicoidal phase relationship. Acoustic tweezers allow for larger manipulation scales, as well as applied forces orders of magnitude higher than their optical counterpart, compensating for their lack of precision.

When the frequency is adequately tuned to manipulate micro-objects, such as mammal cells or bacteria, acoustic tweezers can be used to trap assemblies of thousands of these objects, without affecting their integrity or viability. It is possible to immobilize these objects in a single location of space, in order to analyze them or to culture them, or to apply this effect in a flow, in order to efficiently sort cells of interest (because they are noxious to the others, or because they exhibit interesting properties, such as stem cells) from the bulk. However, the applications of the acoustophoresis phenomenon are still heavily dependent on the fundamental understanding we have of it. While it has been extensively described for a decade, it can be shown that unexpected effects can occur, when light absorption properties are added to the manipulated objects for instance, or when the symmetry of the manipulated objects is lowered below the classic sphere assumption. Since these effects are tag-free phenomena, do not need high energies to happen, and that work with living objects such as red blood cell, algae or bacteria, they may pave the way to an interesting range of applications, such as cancer cell washing or sub cellular cargo delivery.

Biography: 

Gabriel Dumy is a researcher and PhD student at L'Ecole Supérieure de Physique et de Chimie Industrielles de la ville de Paris (ESPCI), where he is investigating the acoustic manipulation of self-propelled nanorobots for biomedical applications.