Analysis of barbiturates by micro-high-performance liquid chromatography with post-column photochemical derivatization

This study attempts to combine the advantages of microcolumn high-performance liquid chromatography (μ-HPLC) with those of post-column photochemical derivatization in barbiturate analysis. Some barbiturates are photochemically unstable, leading to photoproducts that show maximum absorption at 270 nm and not the typical one at ≈220 nm. For this purpose, a laboratory-built photoreactor has been developed to work with μ-HPLC instruments. Its performance is satisfactory in the forensic analysis of barbiturates.