Direct encapsulation

Wei, Y., Xu, J., Feng, Q., Lin, M., Dong, H., Zhang, W.-J. and Wang, C. (2001) A novel method for enzyme immobilization direct encapsulation of add phosphatase in nanoporous silica host materials. Journal of Nanoscience and Nanotechnology, 1, 83-93. 

The spray-dried flavours or powder blends are processed by a roller compactor into lumps (Fig. 21.12). These lumps are crushed into granules. This process cannot be categorised as a direct encapsulating technique, since the flavour-encapsulating effect of compacted flavours is based on the use of spray-dried raw material. 

The thin cylindrical gel was placed in a sealed glass microcapillary of inner diameter of 1.35 mm. As is illustrated in Fig. 2, the capillary was encapsulated in a transparent cell, within which water was circulated to control the temperature. The glass microcapillary with the thin film gel was directly encapsulated in the cell. The temperature was regulated within + 0.05 °C. On the other hand, the film gel with glass plate was directly encapsulated in the transparent cell shown in Fig. 2. In both cases, the temperature of gels was not directly measured, but was obtained by measuring the difference between the circulated water temperature and the temperature of the places where gels were set in. 

In the first step the metal ion is introduced into the zeolite pores by ion exchange or adsorption of a labile metal complex. In the second step the intermediate material is reacted with gaseous complexing ligands, such as 1,2-dicyanobenzene, to form a complex inside the pores that is too large to difiuse out Alternatively metal complexes can be directly encapsulated inside the zeolite cavities during hydrothermal synthesis, as has been shown for FePc, CoPc, NiPc and CuPc in zeolite X [224],... 

Fujiwara M, Shiokawa K, Hayashi K, Morigaki K, Nakahara Y et al. (2007) Direct encapsulation of BSA and DNA into sihca microcapsules (hollow spheres). J. Biomed. Mater. Res. A 81 103-112. 

This technology was recently acquired by National Starch/Ablestik and is finding applications as a laminating resin for printed circuit boards and for chip on board (COB) direct encapsulation of chips, without conventional packaging [31]. 

In order to understand the influence of different molecular parameters on structure formation and stability, we report on the directed encapsulation of two hydrophobic model substrates inside the polymersome shell. The system both complies with requirements like water insolubility and has sufficient fluorescence intensity for monitoring. Fluorescent CdSe/CdS/ZnS core-shell quantum dots (QDs), which carry hydrophobic surface ligands, serve as a model substrate of the nanosize regime (core size approximately 6 nm). Nile Red, a lipophilic fluorescent dye, represents the molecular size regime [268-270]. 

One highly significant appUcalion of transfer molding is the direct encapsulation of electronic components and semiconductor devices. The transfer molding process has the capability, with the correct low-viscosity resin, to successfully mold around incredibly fragile devices and whisker wires. 

Emulsion polymerization techniques have also been used for the direct encapsulation of magnetic particles [113,114]. A double layer of surfactant was generally used (sodium oleate combined with sodium dodecyl benzene sulfonate). The method yielded up to 20 wt% of encapsulated magnetite into polystyrene polydis-perse latex particles. Sometimes, the formation of large amounts of coagulum could not be avoided [113a]. 

Wang YY, Hsieh T-E, Chen IC, Chen CH. Direct encapsulation of organic light-emitting devices (OLEDs) using photo-curable-co-polyacrylate/sihca nanocomposite resin. IEEE Trans Adv Packag 2007 30 421-7. 

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