|Nanocapsules with functionalized surfaces and walls|
Recently a major breakthrough was achieved in the formulation of polymeric artificial nanocapsules. Such capsules can now be made in a reproducible manner having a specific size, shape and in reasonable quantities. This opens a new field of intelligent material with possible sophisticated applications. We expect to bring this research field from the level of basic science to possible application. To achieve this goal we develop the necessary techniques and combine expertise from different fields and laboratories. Now, the first step to allow specific applications is to functionalize the nanocapsules by coating the surface with active sites or to inserting them into the wall. One possible direction is to cover them with lipid membranes providing an artificial cell. We combine these novel technique with recent developments in molecular biology. We will take advantage of natural proteins already optimised by nature for specific tasks and if necessary we will modify them by genetic engineering to adopt them for other purpose. E.g. such nanospheres can harvest specific substrates or release at a specific site encapsulated materials. A second aspect is that these nanocapsules provide a new class of surfaces which will allow to study molecular interactions of surface attached proteins. These studies will permit new types of measurements and provide thus new inside of protein-protein or protein-ligand interaction.
We combine the expertise from different faculties. The group at the Max-Planck Institute for Colloid and Interfaces in Golm (Berlin) has their expertise in the formulation of the polymer shells. They have also a state-of-the-art facility to characterise those particles, the quality of reconstitution and their functionality. Three groups provide the consortium with biological material. The group at the Institute de Pharmacology et Biology Structurale (Toulouse) has their expertise in reconstitution, characterisation and mutagenesis of porins. The group at Universität für Bodenkunde (Vienna) are experts for purification, reconstitution and mutagenesis of S-layer proteins. The group at the Ecole Polytechnique (Lausanne) are experienced with the biochemical manipulation and biophysical characterisation of several membrane spanning receptors (nicotinic acetylcholine receptor, serontonine receptor, G-protein coupled receptors). The group at the Ecole Normale Superieur (Paris) are measuring the tiny forces between e.g. receptor and ligands using micromanipulation of giant vesicles. The group at the Physics department at the University of Genova are experienced with two photon microcopy and force measurements. The group at the Faculty of Engeneering at the University of Porto characterise viscoelastic properties.
A possible application of this type of research is in the field of controlled release. For example, the outcome could be a biosensors to detect and/or remove toxic compounds. The shell can protect encapsulated enzymes against a hostile environment and can be used in various biotechnological applications for environmental protection, for example as cleaning system in waste water to remove toxins or digestion of fats or degradation of other compounds. Moreover, the channel in the shell can be used for 'prefiltering' the substrates to enhance the sensitivity of the enzyme. Such functionalised capsules could be used as sensor for insecticides. Several academic partners do have collaboration with start-ups to transfer the basic knowledge into applications. For example, the Berlin group has recently supported the creation of a start-up Capsulution. The Toulouse group is collaborating with GTP and Nanobiotix.