Manufacturing process, microencapsulation

Particular attention should be paid to nonstandard production technologies including nonstandard methods of sterilization, sterile filtration and aseptic processing, lyophilization, microencapsulation, and certain critical mixing and coating operations. With such processes pilot-scale manufacture may not be predictive of industrial scale manufacture, and data on three full-scale production batches may be required in the application. 

Kaeser-Liard, B. Kissel, T. Sucker, H. Manufacture of controlled-release formulations by a new microencapsulation process, the emulsion-induction technique. Acta Pharm. Technol. 1984, 30 (4), 294-301. 

Formulation and/or development of advanced drug-delivery systems such as microencapsulated molecules, transdermal patches, or liposomes are frequently accomplished in the laboratory. However, large-scale production of these dosage forms may be problematic because the same conditions of manufacture may not be attainable or desirable in the plant setting. Consultation with process development personnel during the finalization of the prototype development phase is one way of minimizing scale-up difficulties. 

The method to manufacture cost-effective displays is to use proper processes for mass production or on a large scale. One example is a roll-to-roll process which needs a flexible substrate to be coated or printed display materials. Here, an important issue is to provide a monolayer of display materials. In order to supply this mono-layer, a variety of methods have been tried for encapsulated cholesteric liquid crystals by Kent Display, microencapsulated electrophoretic... 

Li Shun P, Kowarski CR, Feld KW, Grim WM. Recent advances in microencapsulation technology and equipment. Drug Dev Ind Pharm 1988 14(2,3) 353-376. Robinson RL, Hollenbeck G. Manufacture of spherical acetaminophen pellets comparison of rotary processing with multiple-step extrusion and spheronization. Pharm Tech-nol 1991 15(5) 48-56. 

The final cost of an acceptable, stable, active ingredient - however desirable -is very important to the food manufacturer. Only a few microencapsulation processes available to the food industry combine a relatively low production cost with good shelf life stability and ease of incorporation. 

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