Derivatization chemistries for the determination of inorganic anions and structurally related compounds by gas chromatography - A review

Gas chromatography (GC) methods for the determination of inorganic anions and structurally related compounds are reviewed. In their native form, such analytes are polar and non-volatile, therefore they require derivatization before GC analysis. Several chemistries have been employed to convert anions to volatile molecules with applications to a wide set of analytes: nitrite, nitrate, halides, azide, bromate, iodate, borate, carbonate, thiocyanate, cyanide, sulfide, silicates, phosphates, phosphonates, selenite, selenate, arsenite, arsenate, monomethylarsonic acid, and dimethylarsinic acid have been measured following GC separation. In this review, most derivatization chemistries employed for anions are discussed with attention to molecular aspects of the conversion, experimental conditions, applications to complex sample matrices, and figure of merits.