by Mark Vieceli
Dietary supplement formulas are becoming more sophisticated to meet growing consumer demand for innovations that help products work better and faster. Equally important to such cutting-edge formulas is the dosage form itself.
To keep pace with demand for new offerings, new technologies in capsules—especially hard gelatin and vegetarian hydroxypropyl methylcellulose (HPMC) capsules—have been designed to enhance products’ effectiveness and efficiency. These technologies achieve a natural lifestyle target, help preserve stability, and provide unique delivery profiles and better brand identification.
Latest Innovations
Multi-phase products, where two or more individual components are combined in one dosage form, have been around for decades. However, when brand marketers in dietary supplements started using controlled and targeted release formulations within the last two years, they took on a new life. Unique technologies now provide the opportunity to conveniently deliver two or more components in one capsule for products with multiple-release or targeted-release ingredients.
One format places beads within a liquid-filled capsule. The liquid dose is designed to offer quick release of the liquid ingredients. The beads, typically coated, provide for a controlled or delayed time release. The beads can be floating in liquids, or beads or powders can be contained in an inner capsule suspended in an outer liquid-filled capsule. The thickness of the bead’s coating can be changed so that some beads dissolve as soon as the capsule ruptures, while other beads dissolve later.
Beads offer interesting solutions to various scientific, technical and visual problems that arise when ingredients are suspended in oil. When combined with oils, water-soluble ingredients can turn into an unattractive paste; but, putting these ingredients in bead form will create a more eye-appealing product. Some hygroscopic extracts can cause brittleness in gelatin capsule shells. Formulating the extract into a bead mitigates this problem.
Another design is a liquid capsule within a capsule. Like the beads in a capsule, this format can combine multiple ingredients with different dissolution profiles in a single-dosage form. The capsule-in-a-capsule form is particularly suitable for incompatible ingredients or ingredients that would separate if mixed together. The difference is all the ingredients are in liquid form.
One specific product category that can benefit from a capsule-in-a-capsule approach is for “synbiotic” ingredient combinations—for example, combining a prebiotic and probiotic in one entity. The synergistic interactions are expected to promote optimum digestive health. Specifically, a liquid prebiotic outer layer is released first to prepare the gastrointestinal (GI) tract; the probiotic is the active in the inner capsule, which dissolves later in the intestinal tract where the probiotic is most effective. In this example, the dosage form also serves as a “moisture-defense system,” protecting the probiotic inner capsule in an HPMC capsule suspended in a glycerin formula. This creates an effective barrier to moisture, which helps the probiotic remain inactive until it is ready to go to work.
