In-situ tramadol determination in oral fluid by portable capillary electrophoresis – deep UV fluorescencePagano, Giulia; Loog, Saari Anete; Bolkvadze, Vyacheslav; Gorbatšova, Jelena; Mazina-Šinkar, JekaterinaMicrochemical Journal2026 / art. 116851 https://doi.org/10.1016/j.microc.2026.116851