Study of the lorazepam: cyclodextrin inclusion complexes using electrospray ionization mass spectrometry

As an example of drug–cyclodextrin interactions in aqueous media, the cyclodextrin complexation of lorazepam was studied by electrospray ionization mass spectroscopy (ES-MS). It was concluded that highly concentrated aqueous hydroxypropylcyclodextrins are more suited for the drug complexation and that the inclusion complex includes one molecule of the drug with two and three cyclodextrin molecules as well as two molecules of the drug with three molecules of hydroxypropylcyclodextrins. It was postulated that in the hydroxycyclodextrin cavity the drug molecule decomposes via the elimination of one molecule of formaldehyde.