Carclo develops starch-based hard-shell capsule

Carclo Technical Plastics, a UK-based global supplier of precision injection mouldings, has developed an edible, starch-based hard-shell capsule for pharmaceutical and dietary supplement applications.

The company has worked for five years with its partner, the radio frequency applications group Stanelco, to produce an economically viable alternative to traditional two-piece hard-shell gelatine capsules. Carclo has now successfully manufactured capsules using a new polymer blend developed by Adept Polymers, a Stanelco subsidiary working in conjunction with Stanelco's recent acquisition Biotec Holdings.

Carclo and Stanelco are now seeking to work with third parties to optimise formulations, ensure regulatory approval (for both human and animal consumption) and develop the route to market.

In contrast to the dip moulding process used to produce gelatine capsules, which involves a slow drying process, the injection moulded capsules are ready for filling immediately after manufacture. The capsule has also been designed to offer tamper-evident and novel dissolution features, as well as the possibility of multiple compartments.

The only significant alternative to gelatine currently on the market is hydroxypropyl methyl cellulose (HPMC), a synthetic material with a significantly higher cost base than gelatine, says Carclo. On the other hand, the combination of its starch-based material and the manufacturing process offer a production cost that is competitive with gelatine capsules. In addition, the starch-based hard capsules are claimed to be more resistant than gelatine to heat and humidity, and to facilitate filling because they are non-static.

'This breakthrough has resulted from a combination of Carclo's expertise in precision injection moulding of soluble polymers, Stanelco's expertise in formulating and blending starch-based materials, and the design and development expertise of both organisations,' said Carclo ceo Ian Williamson.

'Stanelco's acquisition of Biotec is enabling the manufacture of materials with significantly lower cost potential than conventional solutions.'