Flow injection analysis voltammetric detection

Wangfuengkanagul and Chailapakul [9] described the electroanalysis of ( -penicillamine at a boron-doped diamond thin film (BDD) electrode using cyclic voltammetry. The BDD electrode exhibited a well-resolved and irreversible oxidation voltammogram, and provided a linear dynamic range from 0.5 to 10 mM with a detection limit of 25 pM in voltammetric measurement. In addition, penicillamine has been studied by hydrodynamic voltammetry and flow injection analysis with amperometric detection using the BDD electrode. 

Voltammetric studies have demonstrated that thiocholine is oxidized at +0.15-0.20 V on CNT-modified GC electrodes as compared to its higher oxidation potential on unmodified GC (+0.7 V), carbon paste (+0.6 V), and gold electrodes (+0.9 V). A lower detection limit of 5 x 10 M thiocholine was obtained under the optimal batch conditions, while the detection limit was further improved down to 3 X 10 M by the electrochemical detection in flow injection analysis. 

J. Wang and B. A. Freiha, Selective Voltammetric Detection Based on Adsorptive Preconcentration for Flow Injection Analysis. Anal. Chem., 55 (1983) 1285. 

A hydrodynamic voltammogram is a current-potential curve which shows the dependence of the chromatographic peak height on the detection potential. The technique used to obtain the necessary information is voltammetric flow injection analysis. in which an aliquot of the analyte is injected into the flowing eluent prior to the detector and the peak current recorded. This is repeated many times, the detector potential being changed after each injection, until the peak current - potential plot reaches a plateau or a maximum, as shown... 

We have developed a new voltammetric method using a quinone reagent [5]. Based on the voltammetry of quinone and acids, we assembled an electrochemical detector for measuring acid concentration at a given potential. The flow injection analysis with electrochemical detection (FIA-ECD) method we developed is preferable, as it is a simpler, more sensitive, and rapid method for acid determination. This chapter assesses this method for determining the acid content in foods and beverages. 

Fuse, T, F. Kusu, and K. Takamura. 1997. Determination of acidity of coffee by flow injection analysis with electrochemical detection./. Agric. Food Chem. 45 2124-2127. Ohtsuki, S., N. Kunimatsu, K. Takamura, and F. Kusu. 2001. Determination of the total acid content in wine based on the voltammetric reduction of quinone. Electroanalysis 13 404-407. 

A positive shift in the voltammetric wave for 2, 4-dichlorophenol was observed on the anodized diamond compared to that at the as-deposited surface [46]. However, relatively stable voltammograms were obtained at anodized diamond, in contrast to those at the as-deposited diamond and GC electrodes, which were deactivated completely by the fifth cycle. The outstanding stability of the diamond electrode was further demonstrated by the electrode response in flow injection analysis. The FIA results for 100 injections of 5 mM 2,4-dichlorophenol at the GC electrode and the anodized diamond electrode were examined at detection potentials of 1.2 V and 1.4 V, respectively. A highly stable detection peak was observed at the anodized diamond the RSD of the peak heights was 2.3 %, and the decrement was 10 %. In contrast, repetitive injections of concentrated 2,4-dichlorophenol... 

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