Comparison in thermal behaviors of homologues, derivatives and adducts of β-cyclodextrin

The thermal behaviors of homologues, derivatives and adducts of β-cyclodextrin (β-CD) are compared based on thermogravimetry (TG) and gas chromatography coupled to time-of-flight mass spectrometry (GC–TOF-MS) analysis. Our results indicate that the number of glucose units and the introduced groups cause a considerable change in thermal decomposition mechanisms of these carbohydrates. Further, it is observed that the mass loss of the bicomponent aggregate formed by phenylarsonic acid (PAA) and β-CD is larger than that of each of the components at higher temperatures. Additionally, the decomposition of the adduct produces a series of arsenic compounds with high relative abundances, such as AsO+, As2O2+, As3O4+ and As4O6+, which is rather different from the decomposition behaviors of free PAA and the adduct of β-CD with sodium arsenite.