Dennis Poncelet 
For correspondence:- Email: poncelet@enitiaa-nantes.fr
Published: 28 June 2007
Citation: Poncelet D. Life is based on a combination of biochemistry and bioencapsulation. Trop J Pharm Res 2007; 6(2):685-686 doi: 10.4314/tjpr.v6i2.1
© 2007 The authors.
This is an Open Access article that uses a funding model which does not charge readers or their institutions for access and distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) and the Budapest Open Access Initiative (http://www.budapestopenaccessinitiative.org/read), which permit unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited..
A long time ago, it was nothing. Then, a big bang dispersed energy over the universe. Some of this energy compacted to form atoms, which combined to form molecules. The molecules became more and more complex, resulting in biochemistry, but life was still not there.
Somebody, let us call Him God, said, let’s try a new thing. Let’s put a microcapsule (membrane) around this biochemistry. Then, life started! Biological cells multiplied, and colonized the earth. They organized themselves to give pluricellular organisms, which evolved to finally become an exceptional structure of more than 1012 microcapsules called a human being.
Bioencapsulation essentially mimicks this very ancient process, i.e.
immobilizing bioactive material (‘actives’), thus avoiding its dispersion in water.
protecting it (against pH, oxygen, etc,.
controlling mass transfer (exchange with the surrounding).
structuring it (change from liquid state to an apparent solid form), and
creating new functions (such as ATP production over mitochondrial membrane).
The challenge of bioencapsulation researchers and engineers is to obtain microcapsules presenting powerful properties and functions like biological cells.
The initial microcapsule concept referred to a liquid core surrounded by a membrane; however, biocapsules may take many different forms such as solid beads, hydrogel beads, liposomes, etc. The core could be a solid, a liquid, an emulsion, or a liquid dispersion in a solid matrix. Some companies even develop small capsules integrated inside larger capsules.
There are a number of methods (and combinations of methods) for producing microcapsules. One simple approach is to classify them as shown in Table 1 (see pdf file) based on the assumption that an encapsulation process comprises of three steps:
Dispersion of the core; either by production of air droplets or liquid dispersion (in the case of a liquid core) or by agitation of a powder and deposition of the coating material on it.
Stabilisation of the capsules; liquid droplets or particles surrounded by a liquid are stabilized by solidifying the external surface (membrane) or the core (beads) via solidification, gellation, polymerization, precipitation, drying or any other physical, physicochemical or chemical process.
Biocapsules may be used for many purposes; specifically, in the medical domain, one could cite:
Taste and odor masking of unflavored drug
Protection of actives against water or oxygen during storage
Enhancement of flow properties of powders in tablet production
Protection of drug against gastric juice and colon delivery of medicines
Formulation of injectable drug form with controlled release profile
Targeting of drug to a specific body site (in cancer therapy)
Chondrocyte immobilization for bone reconstruction
Langerhans islet protection against immune system following implantation for treatment of diabetes.
This is only a short list of potential applications. The domain of applicability is very broad and is likely to expand in the next few years. For additional information, you may connect to the Bioencapsulation Research Group website (http://bioencapsulation.net) where you will find listed relevant books and reviews.
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