The target of this project is to develop a platform of polymer nanoreactors immobilised
on surfaces that will provide new solutions that maintain food quality and safety
through nanotechnology, an emerging technology in food manufacturing. Nanoreactors
are generated by encapsulating enzymes and inserting pH-sensitive channel proteins
in polymer vesicles with sizes in the nanometer range. They are planned for application
as highly sensitive, long-life biosensors to detect early changes in pH or for the release
of antioxidant compounds “on demand” when reactive oxidative species (ROS) affect
food quality. Polymer vesicles provided with pH-sensitive channel proteins that act as
“triggered gates” serve to encapsulate enzymes, the roles of which are to support the
functionality of nanoreactors: they serve as biosensors or to trigger the release of
compounds necessary to preserve food quality. The sensitive detection of pH changes
in the surroundings of nanoreactors via an enzymatic reaction that takes place inside
represents the core of our biosensor. This has the advantages– over biosensors already
in use– of the subsequent amplification of a chemical signal, and long-life due to the
shield provided by the polymer vesicles. The triggered release as a response to the
presence of ROS in the environment of the nanoreactors is based on an encapsulated
enzyme, which acts as a “key” to unblock the protein gate, and allows the release of
antioxidant compounds. Right from the start, combining polymers that are EFSA and
FDA approved together with biomolecules constitutes a safe input to the project, which
will be completed by systematic cell assays relating to the safety of nanoreactors. In
addition, the immobilisation of nanoreactors on surfaces will support their applications
as materials in contact with food matrices, as they will act as “detection surfaces” or as
“active surfaces”.
The concept of antioxidant nanoreactors and the strategy of modulating the properties
of channel proteins, which have already been introduced by us for medical
applications, will serve in the present project for rapid implementation of new chemical
approaches for triggered-functionality nanoreactors. Our food contact systems will
address consumer concerns regarding food quality, because they act only when
required or “on-demand” (pH change or presence of ROS). This represents an elegant
solution in a response-oriented manner as compared to the continual activity that
results from the non-discriminate addition of synthetic or natural antioxidant
molecules.