Direct analysis in real time--high resolution mass spectrometry as a valuable tool for the pharmaceutical drug...

In this study, direct analysis in real time-mass spectrometry (DART-MS) was assessed for the analysis of various pharmaceutical formulations with intention to summarize possible applications for the routine pharmaceutical development. As DART is an ambient ionization technique, it allows direct analysis of pharmaceutical samples in solid or liquid form without complex sample preparation, which is often the most time-consuming part of the analytical method. This makes the technique suitable for many application fields, including pharmaceutical drug development. DART mass spectra of more than twenty selected tablets and other common pharmaceutical formulations, i.e. injection solutions, ointments and suppositories developed in the pharmaceutical industry during several recent years are presented. Moreover, as thin-layer chromatography (TLC) is still very popular for the monitoring of the reactions in the synthetic chemistry, several substances were analyzed directly from the TLC plates to demonstrate the simplicity of the technique. Pure substance solutions were spotted onto a TLC plate and then analyzed with DART without separation. This was the first DART-MS study of pharmaceutical dosage forms using DART-Orbitrap combination. The duration of sample analysis by the DART-MS technique lasted several seconds, allowing enough time to collect sufficient number of data points for compound identification. The experimental setup provided excellent mass accuracy and high resolution of the mass spectra which allowed unambiguous identification of the compounds of interest. Finally, DART mass spectrometry was also used for the monitoring of the selected impurity distribution in the atorvastatin tablets. These measurements demonstrated DART to be robust ionization technique, which provided easy-to-interpret mass spectra for the broad range of compounds. DART has high-throughput potential for various types of pharmaceutical analyses and therefore eliminates the time for sample cleanup and chromatographic separation.