Encapsulations Research

The Institute has been a leader in microencapsulation research, development, and prototype production through most of its 51-year history. SwRI scientists and engineers use physical and chemical encapsulation techniques along with various coating materials that offer specialized microcapsule release characteristics. During 1998, approximately 50 microencapsulation research projects were conducted for the food, nutraceutical (health food), pharmaceutical, cosmetic, personal care, consumer product, agrochemical, veterinary medicine, and chemical industries.

Consumer products make up one of the largest market sectors for the SwRI microencapsulation program. The Institute's contributions in microencapsulation technology have led to advances in detergents, bleaches, carpet cleaners, deodorants, antiperspirants, toothpastes, and paints. Microcapsules prepared for these applications range in size from less than a micrometer to several thousand micrometers.

SwRI scientists conduct microencapsulation research and development for a variety of applications, including industrial, agrochemical, food, and consumer products.

SwRI uses a variety of microencapsulation technologies to produce edible coatings for food components. Encapsulation of acidulants, aromas, bacteria, flavors, nutritional oils and supplements, vitamins, minerals, dietary fibers, leavening agents, and peroxides is used for improved taste and odor masking, for controlled-release applications, or for improved thermal, oxidative, and shelf-life stability.

In the agricultural industry, microencapsulation is increasingly being used to target pest control agents to specific insects and to protect animal feed additives from moisture or air. It also provides safer handling of toxic fungicides and insecticides and controlled release of these agents to increase effectiveness over a prolonged period.

Institute staff members prepared large batches of an encapsulated growth regulator for controlling mosquito larvae, using an interfacial polymerization process. The encapsulation form provided a convenient delivery system and prolonged the field life of the larvicide.

SwRI scientists, working with Enviroquest Ltd. of Cambridge, Ontario, Canada, successfully co-developed and co-patented a microencapsulated medicament for ingestion by honeybees and other beneficial insects. The product was tested in bee hives against tracheal mites. In the study, encapsulated menthol was delivered to honeybees' blood (haemolymph) and killed the mites. The encapsulated menthol also showed excellent shelf life. Additional trials are scheduled, and U.S. Food and Drug Administration approval is pending. SwRI will continue to assist in the development and manufacture of the product.

Aircraft paints and coatings containing an encapsulated stain-inducing additive can disclose possible damage to the aircraft's composite structure by discoloring wherever the surface has sustained an impact.

Microencapsulation of industrial chemicals continues to be a dominant area of research. Microcapsules of catalysts, promoters, and other reactive additives can be manufactured to provide highly stable shelf life prior to their use in adhesives, coatings, paints, sealants, and elastomers.

Working with pharmaceutical and biotechnology companies, Institute engineers and scientists pre-formulated and developed optimal drug dosage formulations. They also used biocompatible, resorbable, and biodegradable polymers to make nanospheres and microspheres for parenteral, injectable, and implantable drug delivery routes. The Institute also developed a variety of controlled-release microcapsule formulations using Food and Drug Administration-approved, stomach-acid soluble coatings for the alimentary tract, or enzymatic degradable materials for oral drug delivery. Institute engineers are also studying formulations that are biodegradable and that can be used for subcutaneous pharmaceutical and cosmetic applications.

1998 Annual Report SwRI Home