Frankfurt, September 24, 2010

Micro-encapsulation :

at Crossroads of Art, Science and Technology

Jean-Antoine Meiners

Laboratoire Meiners Sàrl, 2013 Colombier

Micro-encapsulation : Thinking out of the box

Thinking outside the box is to think differently, unconventionally or from a new perspective.

Micro capsule concepts are the result of the Art of thinking out of the box, the Science to turn imagination into concept and the understanding of Technology to transfer the concept into a product

micro encapsulation

Not all capsules are micro capsules !

micro encapsulation Presentation outline

•  Definitions •  Capsule types •  Release mechanisms •  Examples •  Process •  Physical methods •  Chemical methods •  Complexation •  Discussion

micro encapsulation Definitions

As straightforward and precise as such a definition may sound, the scientific literature and commercial publications typically accept a much broader application field i.e. all sub-millimeter material embedded by a matrix material. Some authors even consider particles of more than one millimeter micro capsules.

Ref. : Jean-A. Meiners, Laboratoire Meiners sàrl

Micro encapsulation is defined as a technology for the packaging of particles of finely ground solids, droplets of liquids, or gaseous materials with the help of protective membranes, also called shell or coating.

Ref. : Prof. Bojana Boh, University of Lubljana

micro encapsulation Definitions

We will use the definition of micro capsules (1 -999 µ) for bodies destined to provide protection against influence from the environment, with a release mechanism destined to make the active substance available at time and place desired.

For the purpose of this presentation we will use the definition of micro spheres for granules that have not as a primary objective the controlled release of their active substance

We will use the definition of micro beads destined to contain the active substance, but being permeable to allow its action to persist.

micro encapsulation Purposes of micro encapsulation

• Protection • Heat, Oxygen,

• Controlled release • Medicine delivery

• Immobilisation • High cell density in bioreactors

• Capsular Perstraction • In Situ Product Removal

• Structuration • Liquid or gas to solid • Dispersability • Dust free

• Functionalisation • Visual aspect • Marketing

What are the desired properties?

•  Size •  Size distribution •  Mechanical strength •  Molecular weight cut- off •  Liquid/ solid core •  Stability (dissolve with time, long- term, etc.) •  Surface properties (neutral, charged, hydrophobic) •  …….etc.

micro encapsulation Capsule types

α : layered with central core β : layered with central void δ : Composite shell γ: Embedded particles

δ α

β γ

Wet and leaky versus dry and tight

Liquid core capsule Solid core capsule

micro encapsulation Capsule types

Solid core

Gas core

Liquid core

Multiwall membrane

micro encapsulation Release mechanisms

Release profiles Triggered release Sustained release

Release mechanisms

Diffusion Dissolution Trigger molecules Thermal Mechanic Osmotic Biochemical

Release effects Immediate Pulsed Delayed

micro encapsulation Entrapment mechanism

micro encapsulation Examples

Bio encapsulation Bio medical cell implants Pharmaceutical targetted delivery Protection micro organisms Seed protection

Flavor and Fragrances encapsulation Phase change liquid - powder Protection volatile molecules Delivery in the consumer item Sensation in the mouth or nose

micro encapsulation Examples

Textile cosmetotextile color change fire retardants

Paper scratch and sniff self copying carbonless paper

Cosmetics skin activated pH dependant delivery system

micro encapsulation Examples

Construction phase change materials

Adhesives multi component

Electrophoretic displays positioning

micro encapsulation Markets of micro encapsulation

Source : Frost & Sullivan 2002

micro encapsulation Examples

Use of micro encapsulation in food and feed manufacturing:

• Survival of micro organisms

• Enzymes and Probiotics

• Thermo sensitive

• Metabolism aW dependent

• Shelf life reduction at ambient conditions

• Difficulties with further processing conditions

micro encapsulation Process

Main principles

Physical

apply a coating on the surface of the substrate Chemical

different polymerisation techniques for entrapment

Complexation inclusion, adsorbtion

micro encapsulation Process

Main principles

Physical apply a coating on the surface of the substrate

• Fluidized bed coating

• Pan coating

• Atomization

• Hybridizing

• Extrusion

• Compacting

micro encapsulation Process

Physical apply a coating on the surface of the substrate

• Fluidized bed coating

micro encapsulation Process

Physical apply a coating on the surface of the substrate

• Fluidized bed coating

micro encapsulation Process

Physical apply a coating on the surface of the substrate

• Fluid Bed agglomeration

micro encapsulation Process

Physical apply a coating on the surface of the substrate

• Pan coating

micro encapsulation Process

Physical methods apply a coating on the surface of the substrate

• Hybridizing

micro encapsulation Process

Physical methods apply a coating on the surface of the substrate

• Extrusion • Double barrel extrusion • Planetary roller extruder • Centrifugal extrusion

micro encapsulation Process

Physical methods apply a coating on the surface of the substrate

• Double barrel extrusion

micro encapsulation Process

Physical methods apply a coating on the surface of the substrate

• Planetary roller extrusion

micro encapsulation Process

Physical methods apply a coating on the surface of the substrate

• Centrifugal extrusion

micro encapsulation Process

Chemical methods different techniques to induce entrapment

• Coacervation methods • Simple coacervation • Complex coacervation • Interfacial coacervation

• Polymerization methods • Interfacial polymerisation • Polymerisation in situ • Matrix polymerisation

micro encapsulation Process

Chemical methods different techniques to induce entrapment

• Coacervation methods

• Formation of macromolecular aggregates as a result of phase separatation – partial desolvation of a homogeneous colloid polymer solution.

• Hardening through

•  crosslinking and formation of new covalent bonds •  non covalent hardening, where hydrogen bonds are formed

between gelatin molecules

micro encapsulation Chemical Methods

micro encapsulation Coacervation

micro encapsulation Chemical Methods

micro encapsulation Chemical Methods

micro encapsulation Chemical Methods

micro encapsulation Chemical Methods

micro encapsulation Chemical Methods

micro encapsulation Chemical Methods

micro encapsulation Chemical Methods

micro encapsulation Complexation

• Cyclodextrin α-cyclodextrin β- cyclodextrin γ- cyclodextrin

• Liposomes

micro encapsulation about Laboratoire Meiners Sàrl

Independant laboratory for discovery and development of Micro encapsulation processes.

Founded :1982 Staff : 9

Laboratories : 250 m2 Affiliated to : University of applied sciences, CH Sion

Active participation in EEC scientific projects. such as Cost 865

Unmatched experience with probiotics and enzymes

THANKS FOR YOUR ATTENTION !!