Analytical techniques such as XRD and XPS provide only structural information. In this respect, Fourier transform infrared spectrophotometer (FTIR) and nuclear magnetic resonance (NMR) diverge from the aforementioned techniques, as they also help to understand the affinities and specificity of drug-excipient interactions on a structural basis. Moreover, they are mainly solution-based approaches, but compatible with solid-state characterization, thus offering two analytical platforms for the price of one . It goes without saying that solution-based analysis is more desirable than solid-state analysis because the former can provide certain quasi-realistic information by partially mimicking in vivo and in vitro conditions. Other advantages in favour of NMR and FTIR are that, unlike XRD, only a few mg of the material are usually sufficient for analysis.