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This article describes an undergraduate laboratory for an instrumental analysis course that integrates electroanalytical chemistry and infrared spectroscopy. Modified electrode surfaces are prepared by constant potentiometric electrolysis over the potential range of 1.5–1.8 V and analyzed by cyclic voltammetry and infrared spectroscopy. The students learned how to prepare a poly(2,2′-bithiophene)-modified platinum sensor electrode for the detection of catechol in the presence of ascorbic acid. The peak separation in the cyclic voltammograms and the shifts of the IR peaks are used to assess the quality of the modified electrode.

Preparation of poly(2,2-bithiophene) modified platinum electrode to detect catechol in the presence of a common interferent have illustrated improved electrochemical reversibility, selectivity and sensitivity compared to conventional electrodes. Cyclic voltammograms and Scanning Electron Microscopy data will be discussed to explain the optimization of preparation of the poly(2,2- bithiophene) -modified platinum electrode for the detection of catechol in the presence of a common interferent such as ascorbic acid.

An overview of ultrahigh‐pressure liquid chromatography (UHPLC) is presented that covers both theoretical and practical aspects of the technique. The push to use higher eluent pressures is the direct result of a new column technology based on the use of smaller diameter separation media and narrower bore diameters in combination with faster linear flow velocities. The topics discussed include the general aspects of the technique, as well as specific information about instrumentation, column design, and nonlinear effects. An important consideration when carrying out UHPLC separations compared to conventional HPLC separations is eluent heating due to compression and decompression heating. In many instances, the amount of heat generated is large and cannot be ignored. Models to predict heating under different operation conditions are discussed.

A newly developed sonogel-carbon electrode was prepared by coating it with a TiO2 sol-gel and heated at 500 ºC. The electrochemical response of the newly developed sonogel-carbon electrode modified with TiO2 was compared to that of an unmodified sonogel- carbon electrode. The modified electrode showed marked enhanced detection of catechol in the prescence of ascorbic acid. Also the sonogel-carbon electrode modified with TiO2 stability was compared to an electrochemically prepared conducting poly(3-methylthiophene) electrode in the detection of catechol over 25 scans. The sonogel-carbon electrode modified with TiO2 was more stable over repetitive scans. This new modified titanium oxide electrode surface could be used in several chemical sensor applications of environmental and biological interest.