Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Synthetic Capsules Made of Natural Building Blocks

Abstract:
Block copolymer vesicles from protein and sugar components

Synthetic Capsules Made of Natural Building Blocks

Bordeaux, France | Posted on March 23rd, 2009

The basis of all life forms are vesicles: membrane-enclosed, liquid-filled "bubbles" made of lipids, proteins, and carbohydrates. Cells, which are separated from the surrounding medium by their cell membrane, are really just big vesicles. Small vesicles play a critical role in the intracellular transport of biomolecules. Synthetic vesicles, such as liposomes and polymersomes, made of lipids and polymers respectively, are used to transport active ingredients in products such as cosmetic or pharmaceutical formulations. They also have potential as microreactors intended to mimic the behavior of living cells. This would be more successful if the vesicles were made of natural components. As reported in the journal Angewandte Chemie, researchers working with Sébastien Lecommandoux and Christophe Schatz at the University of Bordeaux (France) have now attached together blocks of sugar molecule chains (polysaccharides) and protein chains (polypeptides) in a linear fashion. In water, these block copolymers spontaneously form vesicles.

The researchers used dextran, a polymer made of glucose building blocks, and poly(benzyl L-glutamate) (PBLG), a biocompatible polypeptide. By using a series of reactions referred to as "click" chemistry, they attached these molecules to each other blockwise. The advantages of this method are the mild reaction conditions, the nearly quantitative yield, and the fact that other functional side groups on the reactants do not interfere with the reaction.

In this way, the scientists produced block copolymers that combine a polypeptide (protein-like) block and a sugar block. The hydrophobic (water-repellant) polypeptide adopts a helical conformation and in aqueous environments prefers to be side-to-side with those like itself. This results in membrane-like layers that close in on themselves to form spherical vesicles. On both sides of the synthetic membrane, the hydrophilic (water-friendly) dextran chains coil up into a stabilizing "corona". Electron microscope images reveal membranes that are about 21 nm thick surrounding vesicles of a very uniform size (about 45 nm radius).

The researchers would like to use their simple, versatile synthetic strategy to make other synthetic glycopeptides that could be used as model compounds for the exploration of cellular sugar structures (glycomics). The vesicles could also form the basis for a new generation of drug and gene transporters, because their sugar corona binds well to glycoproteins on the surfaces of living cells. The vesicles are also similar to the hulls of viruses and are a first step toward mimicking virus morphology.


Author: Sébastien Lecommandoux, Université de Bordeaux, Pessac (France), recherche.enscpb.fr/lcpo/fr/fichier%20html/perso_lecommandoux-fr.htm

Title: Polysaccharide-block-polypeptide Copolymer Vesicles: Towards Synthetic Viral Capsids

Angewandte Chemie International Edition 2009, 48, No. 14, 2572-2575, doi: 10.1002/anie.200805895


####

Contacts:
Editorial office:

Amy Molnar (US)


Jennifer Beal (UK)


Alina Boey (Asia)

Copyright © Angewandte Chemie

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

Explaining how 2-D materials break at the atomic level January 20th, 2017

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Chemistry

Chemistry on the edge: Experiments at Berkeley Lab confirm that structural defects at the periphery are key in catalyst function January 13th, 2017

Researchers produced nitrogen doped bimodal cellular structure activated carbon December 29th, 2016

Safe and inexpensive hydrogen production as a future energy source: Osaka University researchers develop efficient 'green' hydrogen production system that operates at room temperature in air December 21st, 2016

Scientists boost catalytic activity for key chemical reaction in fuel cells: New platinum-based catalysts with tensile surface strain could improve fuel cell efficiency December 19th, 2016

Possible Futures

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

Explaining how 2-D materials break at the atomic level January 20th, 2017

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Nanomedicine

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

'5-D protein fingerprinting' could give insights into Alzheimer's, Parkinson's January 19th, 2017

New active filaments mimic biology to transport nano-cargo: A new design for a fully biocompatible motility engine transports colloidal particles faster than diffusion with active filaments January 11th, 2017

Announcements

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Ultra-precise chip-scale sensor detects unprecedentedly small changes at the nanoscale January 20th, 2017

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project