How biological capsules respond under stress

October 28, 2011

Cosmetics and pharmaceutical drug delivery systems could be improved thanks to a new method developed to precisely measure the capability of capsule-like biological membranes to change shape under external stress. This work is outlined in a study about to be published in European Physical Journal E by Philippe Meleard and Tanja Pott from the Rennes-based Institute of Chemical Sciences at the European University of Brittany and their colleagues from the Center for Biomembrane Physics at the University of Southern Denmark in Odense.

The authors found that, by using a statistical method, they could evaluate the bending elasticity of biological models, a key factor in understanding their physical properties. They relied on a series of video-microscopy images of giant liposomes, which are artificial spherical vesicles of more than ten micrometers in diameter made of a bi-layer of fatty substance called lipids. They studied the membrane deformations triggered by thermal agitation of molecules in the liquid surrounding them, over time.

Previous approaches used the average of deformation amplitudes observed in these images, which meant a loss of accuracy of up to 20 percent. Instead, in this study, the authors focused on evaluating the statistical distribution of the membrane deformation, which yielded unprecedented precision. This method relies on the so-called Maxwell-Boltzman statistical distribution, named after James Clerck Maxwell and Ludwig Boltzmann, who studied the kinetic theory of gas using this approach.

The method presented in this paper could be of interest to industry scientists in devising both cosmetic and pharmaceutical applications. For example, industry often needs to encapsulate products such as cytotoxic or in prior to delivering them into patients' bodies. Ultimately, it could help industry scientists determine what type of biological membrane is best suited for their specific purpose.

Explore further: Scientists devise method to study membrane proteins

More information: Méléard P et al. (2011) Advantages of statistical analysis of giant vesicle flickering for bending elasticity measurements. European Physical Journal E. 34: 116 (DOI 10.1140/epje/i2011-11116-6)

Related Stories

Scientists devise method to study membrane proteins

April 14, 2004

Scientists at the University of Virginia Health System have come up with a protocol to extract proteins from membranes by using chemicals that allow them to be reversibly folded and refolded. The proteins can then be studied ...

Biologists search for 'half-fusion'

May 16, 2005

Every living cell is surrounded by a membrane, a thin barrier that separates the genetic machinery of life from the non-living world outside. Though barriers, membranes are not impervious. Cells use a complex hierarchy of ...

Together, biological membranes prevail

January 26, 2007

Researchers at the University of Illinois at Urbana-Champaign have developed a novel method to visualize the fusion of biological membranes at the single-event resolution. Observing the individual fusion events revealed an ...

Major step for drug discovery and diagnostics

February 12, 2009

Researchers from Nano-Science Center, University of Copenhagen and National Centre for Scientific Research, France have developed a general method to study membrane proteins. This method can be used to screen several thousand ...

Live recordings of cell communication

August 6, 2009

Neurons communicate with each other with the help of nano-sized vesicles. Disruption of this communication process is responsible for many diseases and mental disorders like e.g. depression. Nerve signals travel from one ...

Recommended for you

Scientists paint quantum electronics with beams of light

October 9, 2015

A team of scientists from the University of Chicago and the Pennsylvania State University have accidentally discovered a new way of using light to draw and erase quantum-mechanical circuits in a unique class of materials ...

Using optical fiber to generate a two-micron laser

October 9, 2015

Lasers with a wavelength of two microns could move the boundaries of surgery and molecule detection. Researchers at EPFL have managed to generate such lasers using a simple and inexpensive method.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.