Electrochemical analytical chemistry

Laboratory of Electrochemical Methods, Analytical Chemistry Department, Faculty of Chemistry, Moscow State University, 119992, Lenin Hills, Moscow, Russia Karyakin chem.msu.ru... 

Figure 2 Selective electrochemical detection of a mixture on multielectrode amper-ometry. AA = Ascorbic acid, NE = norepinephrine, DOPAC = 3-4-dihydroxy-phenylacetic acid, E = epinephrine bitartrate, 5-HIAA = 5-hydroxyindole-3-acetic acid, HVA = homovanillic acid, TRP = tryptophan, 5-HT = 5-hydroxytryptamine, and 3-MT = 3-methoxytyramine (separated by RPLC). Detection was with a 4-electrode glassy carbon array, with electrode 1 at 500 m V) electrode 2 at 700 mV, electrode 3 at 900 mV, and electrode 4 at 1100 mV. Note that at electrode 1, HVA, TRP, and 3-MT are not seen. At electrode 2, only TRP is not seen. A standard calomel electrode was used as reference. (Reprinted with permission from Hoogvliet, J. C., Reijn, J. M., and van Bennekom, W. P., Anal. Chem., 63, 2418, 1991. 1991 Analytical Chemistry.)...

Principles and Characteristics A substantial percentage of chemical analyses are based on electrochemistry, although this is less evident for polymer/additive analysis. In its application to analytical chemistry, electrochemistry involves the measurement of some electrical property in relation to the concentration of a particular chemical species. The electrical properties that are most commonly measured are potential or voltage, current, resistance or conductance charge or capacity, or combinations of these. Often, a material conversion is involved and therefore so are separation processes, which take place when electrons participate on the surface of electrodes, such as in polarography. Electrochemical analysis also comprises currentless methods, such as potentiometry, including the use of ion-selective electrodes. 

M.T. Domenech Carbo, M.J. Casas Catalan, A. Domenech Carbo, R. Mateo Castro, J.V. Gimeno Adelantado, F. Bosch Reig, Analytical Study of Canvas Painting Collection from the Basilica de la Virgen de los Desamparados using SEM/EDX, FT IR, GC and Electrochemical Techniques, Fresenius Journal of Analytical Chemistry, 369,571 575 (2001). 

Royce W. Murray is Kenan Professor of Chemistry at the University of North Carolina at Chapel Hill. He received his B.S. from Birmingham Southern College in 1957 and his Ph.D. from Northwestern University in 1960. His research areas are analytical chemistry and materials science with specialized interests in electrochemical techniques and reactions, chemically derivatized surfaces in electrochemistry and analytical chemistry, electrocatalysis, polymer films and membranes, solid state electrochemistry and transport phenomena, and molecular electronics. He is a member of the National Academy of Sciences. 

Much of the study of ECL reactions has centered on two areas electron transfer reactions between certain transition metal complexes, and radical ion-annihilation reactions between polyaromatic hydrocarbons. ECL also encompasses the electrochemical generation of conventional chemiluminescence (CL) reactions, such as the electrochemical oxidation of luminol. Cathodic luminescence from oxide-covered valve metal electrodes is also termed ECL in the literature, and has found applications in analytical chemistry. Hence this type of ECL will also be covered here. 

The potential of ECL in analytical chemistry has only more recently been investigated, but has rapidly gained recognition as both a sensitive and selective method of detection. Most reported applications have utilized the tris(2,2 -bipyri-dyl) ruthenium(II) [Ru(bpy)32+] ECL reaction, or else the electrochemical initiation of more conventional CL reactions, but many other potentially useful systems have been investigated. The applications of ECL in analytical chemistry have recently been the subject of comprehensive reviews [12-16],... 

J. of Electro-analytical Chemistry, 471 116- 125 King, F., Quinn, M. J., Litke, C. D., 1995. Oxygen reduction on copper in neutral NaCl solution. Journal of Electro-analytical Chemistry, 385(1) 45 - 55 Kneer, E. A., 1997. Electrochemical measurements during the CMP of Tungsten thin films. J. Electrochem. Soc., 144 3041 - 3049... 

The results obtained with NaCl at 25°C and with KCl at 25°, 35° and 45°C in Eastman Kodak 398-3 cellulose acetate are listed in Table I. When examining the data it should be remembered that the fixed charge capacity measured here is that effective in electro-kinetic properties of the membrane it is not a quantity of analytical chemistry. Nevertheless, because NaCl and KCl are very similar in their electrochemical properties, one would expect the apparent number of moles of fixed charges per unit mass of dry... 

J. Barek, J. Cvacka, A. Muck, V. Quaiserova and J. Zima, Electrochemical methods for monitoring of environmental carcinogens. Fresenius Journal of Analytical Chemistry, 2001, 369(7-8), 556-562. 

Ewing AG, Mesaros JM, Gavin PE. Electrochemical detection in microcolumn separations. Analytical Chemistry 66, A527-A537, 1994. 

Pihel K, Hsieh S, Jorgenson JW, Wightman RM. Electrochemical detection of histamine and 5-hydroxytryptamine at isolated mast-ceUs. Analytical Chemistry 67,4514-4521, 1995. 

Zhao, M, Hibbert, D B, and Gooding, J J (2003), Solution to the problem of interferences in electrochemical sensors using the fill-and-flow channel biosensor. Analytical Chemistry 75 (3), 593-600. 

Note Each year the August 15 issue of Analytical Chemistry contains extensive listing of suppliers of electrochemical instruments, electrodes and accessories, with current phone numbers. 

Despite the pervasive use of electrochemical sensors and the fundamental importance of electrochemistry as a division of physical and analytical chemistry, this field of study has not traditionally been a favorite of students. One reason for this could be the fact that most electrochemical and electroanalytical textbooks introduce electrochemistry by explaining first the thermodynamics of the electrochemical cell. That approach is bound to discourage all but the brave few. 

The book covers the entire field of electrochemical (bio)sensor design and characterization and at the same time gives a comprehensive picture of (bio)sensor applications in real clinical, environmental, food and industry-related samples as well as for citizens safety/security. In addition to the chapters, this volume offers 53 step-by-step procedures ready to use in the laboratory. This complementary information is offered on a CD-ROM included with the book in order to facilitate hands-on information on the practical use of electrochemical biosensor devices for the interested reader. It is the first time that the Comprehensive Analytical Chemistry series offers such complementary information with detailed practical procedures. 

For about 90 years, we assist to the emergence and the development of analytical chemistry, in which voltammetry occupies a central place. During this period, many electrochemical methods have been proposed to improve the performances, and simple and effective equipments have been designed, developed and marketed. The milestones of these progresses are summarized in Table 8.1. Lastly, theoretical treatments allowed to establish the general laws, giving the equations that connect various experimental parameters to the concentrations. 

In recent years, electrochemical genosensors developed on the principle of nanotechnology have become one of the most exciting forefront fields in analytical chemistry due to the recent advances in... 

M.I. Pividori and S Alegret, Electrochemical genosensing of food pathogens based on graphite epoxy-composite. In S. Alegret and A. Merkogi (Eds.), Comprehensive Analytical Chemistry, Vol. 49, Elsevier, 2007, pp. 437-464. 

Most electrochemical immunosensors use screen-printed electrodes produced by thick-film technology as transducers the importance of screen-printed electrodes in analytical chemistry is related to the interest for development of disposable and inexpensive immunosensors. A thick-film is based on the layers deposition of inks or pastes sequentially onto an insulating support or substrate the ink is forced through a screen onto a substrate and the open mesh pattern in the screen defines the pattern of the deposited ink. 

This chapter presents an approach to perform enzyme linked immunosorbent assays (ELISA) in a microfluidic format with electrochemical detection. This field of analytical chemistry has shown a strong activity in recent years, and many reports have presented the use of capillary-sized reactors for running immunoassays either in homogeneous format (where the antigen-antibody complex and the labelled revelation reagents are separated prior to detection, as for instance by capillary electrophoresis [1-3]) or in heterogeneous format (where the antibody is immobilised on the inner surface of the microsensor device [4] or on microbeads [5,6]). 

---