Some analytical techniques, such as voltammetry, are relatively little used in undergraduate experimental disciplines in chemistry (and related sciences), although addressed in theoretical ones. Since, in contrast to what one thinks, voltammetric measurements are still often used in routine analysis, some of the most direct techniques will be highlighted in this text, with suggestions to the reader who seeks more knowledge on this theme. The experiments presently proposed present a well defined conceptual and methodological character and have been tested in the experimental classes of the Instrumental Analytical Chemistry discipline of the Institute of Chemistry at UNICAMP. Each module is proposed for four hours of activities in the laboratory, with low risk.

Keywords
voltammetry, water, sugarcane liquor, fruit juices, nickel, cobalt, copper, cadmium, zinc, ascorbic acid

Authors
João Carlos de Andrade
Audrey de Arruda Falcão
Elaine Castilho Guedes
Universidade Estadual de Campinas, Instituto de Química

Translated by
João C. de Andrade

Revised by
Carol H. Collins

Warning

Attention: “Read carefully the procedure before starting the experiment. Do not perform the experiment without being monitored by your teacher. In doubt ask for help!”

This text will introduce the main voltammetric methods of analysis, from its basic aspects to applications in trace analysis. The techniques to be presented are continuous current (polarographic; DC, direct current), sampled direct current (sampled DC), normal pulse (NP, normal pulse), differential pulse and square wave voltammetry. The use of voltammetry in trace analysis is discussed using anodic / cathodic stripping and adsorptive stripping voltammetry. Aspects related to the matrix effects and to method validation will also be discussed.

Keywords
polarography, voltammetry, anodic stripping voltametry, cathodic stripping voltametry, adsorptive stripping voltammetry, matrix effects, method validation

Autor
Luiz Manoel Aleixo (in memoriam)
Universidade Estadual de Campinas, Instituto de Química

Translated by
João C. de Andrade

Revised by
Carol H. Collins