Simultaneous Determination of Uric Acid and Caffeine by Flow Injection Using Multiple-Pulse Amperometry

The present study reports the development and application of a flow injection analysis (FIA) system for simultaneous determination uric acid (UA) caffeine (CAF) using cathodically pretreated boron-doped diamond electrode (CPT-BDD) multiple-pulse amperometry (MPA). electrochemical profiles UA CAF were analyzed via cyclic voltammetry in potential range 0.20–1.7 V 0.10 mol L−1 H2SO4 solution as supporting electrolyte. Under optimized conditions, two oxidation peaks at potentials 0.80 1.4 observed; these yielded concentration linear ranges 5.0 × 10−8–2.2 10−5 10−8–1.9 limits detection 1.1 10−8 1.3 CAF, respectively. proposed method exhibited good repeatability stability, no interference was detected signals presence glucose, NaCl, KH2PO4, CaCl2, urea, Pb, Ni, Cd. FIA-MPA environmental samples resulted recovery rates ranging between 98 104%. results obtained showed that BDD sensor analytical performance when applied determination, especially compared to other sensors reported literature.