Metabolomics investigations towards formulated natural complex products by untargeted and targeted mass spectrometry-based approaches

Although the last decade has witnessed a marked growth in the market of plant-based natural products, their high complexity in terms of composition makes a challenging task the guarantee of quality, efficacy and safety requirements. In such scenario, the recently approved European regulation EU 2017/745 has created a breaking point in the regulation of medical devices forcing the manufactures to investigate the overall qualitative composition of devices made of substances and quantitative information for the main constituents or for the components responsible for the desired effect. In view of this stricter standardization of plant-based medical devices, an intense research towards advanced technologies and robust analytical protocols is required. Based on these considerations, Grintuss® syrup was selected as a case study of formulated natural complex products for quali-quantitative metabolomics investigations. In particular, in the first part, an untargeted metabolomic approach for monitoring the batch-quality of Grintuss® syrup by electrospray ionization mass spectrometry flow injection analysis was developed. After having assessed the validity of the model by using multivariate statistical process control, the quality verification of new batches under investigation was achieved by comparing their profile with the fingerprinting profile of batches prepared according to the optimized and validated manufacturing process. The second task was aimed at profiling the metabolites contained in Grintuss® syrup by applying a targeted metabolomic LC-MS-based approach. Thus, an in-house database of high-purity standard reference compounds was built. Then, after the acquisition of MS/MS spectra of standard compounds of interest, the matching between the detected metabolites from samples and standard reference compounds from the database was assessed. Finally, the quantitative analysis of the recognized metabolites was performed and the results thus achieved have been combined with information deriving from the analysis of additional compounds allowing to reach the knowledge of >99.9% of the overall composition of Grintuss® syrup.