▶ Excipient compatibility screening
Excipients are indispensible for a tablet formulation. There are numerous excipients with different chemical functionalities and diverse physiochemical properties that may be selected for a given compound. It is important to carefully evaluate the potential of different excipients, and rationally choose compound combinations that represent a safe way forward in terms of chemical compatibility and/or physical stability. Based on our extensive experience, main areas listed as follows can be evaluated: API-excipient interaction Existence of functional excipients may affect the dissolution, decomposition, hydroscopicity, mechanism of action, and other properties of the API. In some cases excipients may even induce a change in the polymorphic form of the API resulting in complete alteration of the desired and selected properties. H-bonding was formed between API and HPMC (left), and the morphology of API altered (right). Further reading: Tian F, Baldursdottir S, Rantanen J, Molecular Pharmaceutics 2009, 6: 202–210 Influence of excipients on the drug behavior Dissolution of API was decreased by the presence of excipients PEG and HPMC Further reading: Tian F, Sandler N, Aaltonen J, Lang C, Saville D, Gordon K, Strachan C, Rantanen J, Rades T, Journal of Pharmaceutical Sciences 2007，96: 584-94