University of Cambridge > Talks.cam > Cambridge Society for the Application of Research (CSAR) > Bacteria as Active Colloids

Bacteria as Active Colloids

Add to your list(s) Download to your calendar using vCal

If you have a question about this talk, please contact Dr Nigel Bennee.

A colloid is a suspension of particles in a liquid that, despite being heavier than the liquid, can nevertheless remain suspended against gravity because of thermal (or Brownian) motion. Colloidal particles have sizes in the range of 10 nm to just over 1 micron. Interestingly, the vast majority of bacteria have sizes in the upper end of this range. Thus, bacteria are colloids. But they do things that ordinary colloids do not do. In particular, they can grow and divide, and they are capable of self-propelled motion (‘swim’). To a physicist, then, a suspension of bacteria can be considered an ‘active colloid’. In this lecture, we will first speculate briefly whether there are reasons why bacteria – the smallest known autonomous living organisms – must necessarily be colloidal in size, before moving on to examine bacteria as active colloids. We will see how the growth of a bacterial colony and the aggregation of motile bacteria can be seen as novel self assembly processes whereby micron- sized ‘particles’ can be harnessed to generate structures spontaneously.

This talk is part of the Cambridge Society for the Application of Research (CSAR) series.

Tell a friend about this talk:

This talk is included in these lists:

Note that ex-directory lists are not shown.

 

© 2006-2014 Talks.cam, University of Cambridge. Contact Us | Help and Documentation | Privacy and Publicity