Medical compounding applications are growing in volume and sophistication. Jennifer Markarian looks at new developments using a variety of active components
Healthy growth for medical compounding
The use of compounding extruders is growing in some very different segments of the medical industry. Application areas such as diagnostic equipment housings, hospital equipment, medical devices and pharmaceuticals each have their own formulations, requirements and regulations. Compounding has for some time been used to
incorporate ingredients such as radiopaque additives and custom colours in materials for healthcare equipment and medical devices, but now a greater variety of polymers and additives are being used. For example, antimicrobial additives are increasingly being added to compounds for devices such as catheters and medical equipment housings (see “Specifying silver antimicrobials for medical devices” in Compounding World, February 2012, page 33). Another growing application area is the compound- ing of bioresorbable polymers. Tony Listro, managing director at Foster Delivery Science, a pharmaceutical contract organization that specializes in hot-melt extrusion for drug delivery, explains that bioresorbable compounds are used in medical devices such as bone
screws and anchors. They are meeting growing demands for bioresorbable implants, especially in orthopaedics. ConMed Linvatec Biomaterials of Finland is also
active in this market and is using a KraussMaffei Berstorff Ultra Glide laboratory twin-screw extruder to produce bioresorbable polymers based on polylactic acid (PLA). The company manufactures a range of implants under cleanroom conditions, including screws, plates or pins for fixing broken bones. As the bone heals, the implants biodegrade and are absorbed by the body. This helps the healing process and eliminates the need for repeat surgery to remove the implant. In such compounds, the plastic matrix is the functional piece, but the compound often includes a bone growth additive. Active pharmaceutical ingredients (APIs) are also being compounded into polymers for medical devices in which they deliver localized, controlled release, such as some implants (long-term devices) or catheters (short-term devices) that release anti-inflammatory drugs. One of the most recent emerging technologies is