Instrumental analysis and molecular modelling of inclusion complexes containing artesunate

A series of five guest–host inclusion complexes containing the antimalarial and anticancer agent artesunate (ATS) were obtained and characterized in the present study. Different cyclodextrins (CDNs) were used as hosts [α-cyclodextrin (CDN1), β-cyclodextrin (CDN2), γ-cyclodextrin (CDN3), (2-hydroxypropyl)-β-cyclodextrin (CDN4) and (2-hydroxypropyl)-γ-cyclodextrin (CDN5)], and the formation of the adducts was simulated using molecular modelling. The results indicating the hypothetical formation of all complexes were confirmed on the prepared samples by FTIR spectroscopy and thermal analysis (TG—thermogravimetric/DTG—derivative thermogravimetric/HF—heat flow). Our results showed that the partially entrapment of ATS inside the cavity of each cyclodextrin is a consequence of H-bonds formation, electrostatic interactions (dipole–dipole) and hydration water substitution. Also, all complexes formed in a 1:1 molecular ratio presented with higher thermal stability than pure ATS, making the analysed adducts possible alternatives in the drug design process of new and improved pharmaceutical formulations containing ATS.