a b s t r a c tA photoelectrochemical detector (PECD) was developed for determination of organic compounds in flow injection analysis (FIA) and high performance liquid chromatography (HPLC) based on the extraordinary oxidation power of nanostructured TiO 2 photoanodes under UV illumination. The PECD is a simple, small, and compact photoelectrochemical cell consisting of low cost components such as a TiO 2 nanostructured photoanode and a UV-LED. Compared with conventional FIA and HPLC selective detectors, such as UV-Vis detector, electrochemical detector and fluorescent detector, the PECD has the advantage of being low cost, non-selective and sensitive. Using the FIA mode, the analytical principle of the PECD was demonstrated by detecting a large variety of organic compounds, such as sugars, amino acids, alcohol, straight chain carboxylic acids, and aromatic carboxylic acid. The PECD was subsequently coupled with a typical FIA and HPLC system for the determination of sugars. For the application in FIA, under the optimum experimental conditions, the linear ranges for glucose and sucrose were 25-600 lM and 25-500 lM, respectively, with the same detection limit of 10 lM. When the PECD was coupled with a HPLC system, the linear range for both glucose and sucrose was 7.5-200 mM with the same detection limit of 1 mM under the optimal experimental conditions.