This work presents a group of high-quality hydrophilic and negatively charged coated, iron oxide magnetic nanoparticles (MNPs) that have been prepared using a microwave-ultrasound-assisted protocol, and demonstrates the great impact that the synthetic strategy has on the resulting MNPs. The different coatings tested, including citric acid, carboxymethyl dextran and β-cyclodextrin (βCD)/citric acid have been compared and have shown good dispersibility and stability. The ability of βCD to maintain the inclusive properties of the coated MNPs has been proven as well as their cytocompatibility. An amino citrate-modified βCD is proposed and its capabilities as a flexible amphoteric adsorbing device have been studied. The NMR relaxometric properties of the coated MNPs have been investigated using field-cycling nuclear magnetic relaxation dispersion profiles. For the amino citrate-modified βCD system, the order of magnitude of the Néel relaxation time is in the typical range for superparamagnetic systems' reversal times, i.e., 10⁻¹⁰–10⁻⁷ s. The r_d value corresponds to the physical radius of the magnetic core, suggesting that, in this particular case, the coating does not prevent the diffusive motion of water molecules, which provide the basis for potential future magnetic resonance imaging (MRI) applications.

Compounds that contain (R)-3-amino-4-(2,4,5-trifluorophenyl)butanoic acid substituted with bicyclic amino moiety (2-aza-bicyclo[2.2.1]heptane) were designed using molecular modelling methods, synthesised, and found to be potent DPP-4 (dipeptidyl peptidase-4) inhibitors. Compound 12a (IC50 = 16.8 ± 2.2 nM), named neogliptin, is a more potent DPP-4 inhibitor than vildagliptin and sitagliptin. Neogliptin interacts with key DPP-4 residues in the active site and has pharmacophore parameters similar to vildagliptin and sitagliptin. It was found to have a low cardiotoxic effect compared to sitagliptin, and it is superior to vildagliptin in terms of ADME properties. Moreover, compound 12a is stable in aqueous solutions due to its low intramolecular cyclisation potential. These findings suggest that compound 12a has unique properties and can act as a template for further type 2 diabetes mellitus drug development.