Freeze drying is becoming a popular preservation technique for manufacturers of pharmaceutical and phytochemical products because it effectively prevents or slows most chemical and bio-chemical reactions, and maintains delicate biological structures. Beyond assuring shelf life, the technology can precipitate product innovation, as well.
Take the case Carrington Laboratories, a research-based pharmaceutical and medical device company in Irving, TX, engaged in isolating and developing naturally occurring complex carbohydrates. A few years ago, when researchers were developing a line of non-stick wound dressings using carbohydrates derived from Aloe vera, they began exploring freeze drying as means of providing the products with a substantial shelf life. Their initial IDEA was to freeze dry their product to effectively control degradation, but a collaboration with Oregon Freeze Dry of Albany, OR, allowed Carrington to use the technology to provide the advantage of a soothing gel in a solid form.
"Our partnering with Oregon Freeze Dry successfully produced two unique products that complement our line of wound care products," says Dr. Bill Yates, Executive Director of Research and Development at Carrington, which manufactures and markets more that 75 application-specific products for use in hospitals, home healthcare and extended care facilities.
The result of Carrington's collaboration with Oregon Freeze Dry is two wound care gels, the CaraSorb^TM M Freeze-Dried Gel wound dressing and an oral bandage for canker sores.

With the CarraSorb M, "because freeze drying removes all water from the dressing it instantly resolubilizes into a soothing, healing gel on contact with a exudating wound," Yates says. "It is a solid form of pure gel when freeze dried, so it doesn't need a fiber covering to hold it in place. By developing and marketing a freeze-dried gel for wound care we solved the need for different moisture levels at different points in the application and treatment process." CarraSorb M is a four-inch diameter dressing, containing acemannan hydrogel processed from Aloe vera (L.). Because the dressing does not need fiber coverings, there are no fiber residues to become contaminated and stick to the wound when the dressing is changed. Once it is placed on a wound, CarraSorb M reconstitutes into a gel, absorbing excess moisture and keeping the surrounding skin clean and dry. The dressing is used to treat pressure ulcers; foot, diabetic and stasis ulcers; radiation dermatitis; and post-surgical incisions. "Oregon Freeze Dry also assisted in the development of our proprietary Mylarfoil packaging which protects the dressings from atmospheric moisture and to extend shelf life, "Yates says.
Freeze drying is process in which product is frozen and water is extracted through sublimation. To freeze dry a product, it is first completely frozen before entering   Next Page | Back to R&D page