PW: What issues or trends do you see developing with regard to pharmaceutical packaging materials?
Bauer: Number one is the need for improved barriers. Standard blister materials will need to be stronger in protecting newer drugs from moisture and oxygen.
Cold-formed aluminum is the standard for providing a complete barrier, but many people don’t like the opaque look of the blister, or its size. PCTFE (polychlorotrifluoroethylene), cyclic olefin copolymers, and polyvinylidene chloride represent some examples of existing barrier materials that meet more stringent demands. These materials provide high moisture and oxygen barriers, but thus far, the improvements have been primarily through increased material thickness. The use of desiccants and oxygen scavengers in the film, or the use of plasma coatings on PET or PVC, represent new ideas that may also work to increase barrier performance. Some companies are using computers to conduct Finite Element Analysis. The computer models how a blister cavity will form, and how much thinning of material will take place in each area of the blister. This permits the computer to predict permeation of the blister. For confirmation of results, a blister can be protoyped and a cross-section measurement of materials thickness taken to determine if the simulation was accurate. The blister’s performance can be tested. As the company gains knowledge, it can predict blister performance through the computer simulation, without the trial and error of testing on packaging materials, or trial and error making expensive blister tools, thereby reducing costs.
