Encapsulating Encapsulation

The development of a successful encapsulation system for a target application requires knowledge about the stability of the chosen bioactive (core) the properties of the materials used for encapsulation (encapsulant) and the suitability of the delivery system (microcapsule) for its final application. Table 24.1 gives a summary of important considerations. 

Although it is most remarkable that gases can be encapsulated, encapsulation may be accomplished with any substance which can enter the zeolite at the higher temperature. 

Encapsulation. Encapsulation is a technique that allows the cells or tissues from the donor animal to be separated from the human immune system. Usually it does not literally involve a capsule but rather drop>-lets of a viscous gel derived from a nonanimal source such as seaweed. The gel allows the grafted cells to accept nutrients from the human recipient and to diffuse hormones, such as insulin, into the body. At the same time, it protects the grafted cells from attacking antibodies. Encapsulation is not a viable technique for whole organ xenografts. 

Cyclodextrins form crystalline inclusion complexes with many organic compounds, including some gases, which are bound within the molecule. Formation of these complexes is called encapsulation. Encapsulation results in a change of the physico-chemical properties of encapsulated compounds (e.g. volatility of flavour-active compounds and their increased stability against oxidation and photodegradation). Cyclodextrins are, therefore, of greatest use as carriers (encapsulators) of odoriferous substances, emulsion stabilisers and are also used to remove bitter substances from citrus juices (see Section 8.3.5.1.1). 

Encapsulation Encapsulation by Encapsulation by insoluble minerals somewhat soluble minerals (i.e., quariz) (i.e., Fe-oxides) Encapsulation by soluble minerals (i.e., Fe-sulfates)... 

A number of refinements and applications are in the literature. Corrections may be made for discreteness of charge [36] or the excluded volume of the hydrated ions [19, 37]. The effects of surface roughness on the electrical double layer have been treated by several groups [38-41] by means of perturbative expansions and numerical analysis. Several geometries have been treated, including two eccentric spheres such as found in encapsulated proteins or drugs [42], and biconcave disks with elastic membranes to model red blood cells [43]. The double-layer repulsion between two spheres has been a topic of much attention due to its importance in colloidal stability. A new numeri-... 

The HLB system has made it possible to organize a great deal of rather messy information and to plan fairly efficient systematic approaches to the optimiza-tion of emulsion preparation. If pursued too far, however, the system tends to lose itself in complexities [74]. It is not surprising that HLB numbers are not really additive their effective value depends on what particular oil phase is involved and the emulsion depends on volume fraction. Finally, the host of physical characteristics needed to describe an emulsion cannot be encapsulated by a single HLB number (note Ref. 75). 

Metallofullerenes are commonly found witli [74], [76], [80] and [82] fullerene and span composites tliat have a single (Mf2 Cg2), two or even tliree metal atoms encapsulated. The first type of... 

Fergason J L 1984 Encapsulated liquid crystal and method US Patent 4 435 047... 

Li W, Virtanen J A and Penner R M 1995 Self-assembly of n-alkanethiolate monolayers on silver nanostructures protective encapsulations Langmu/r 11 4361... 

NAMD was implemented in an object-oriented fashion (Fig. 3). Patches, the encapsulated communication subsystem, the molecular structure, and various output methods were objects. Every patch owned specialized objects... 

Fig. 3. NAMD 1 employs a modular, object-oriented design in which patches communicate via an encapsulated communication subsystem. Every patch owns an integrator and a complete set of force objects for bonded (BondForce), nonbonded (ElectForce), and full electrostatic (DPMTA) calculations.

Flexible foams are used in mattresses, cushions, and safety applications. Rigid and semiflexible foams are used in structural applications and to encapsulate sensitive components to protect them against shock, vibration, and moisture. Foam coatings are tough, hard, flexible, and chemically resistant. 

Casting resin Thermoplastic elastomer Cast resin, flexible Mineral- and/or glass-filled Epoxy molding and encapsulating compound Polystyrene... 

Plastic bags Plastic beads Plastic bearing materials Plastic cements Plastic drums Plastic electronic package Plastic encapsulant... 

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