Environmental analysis by electrochemical sensors and biosensors fundamentals

Nanostructure Science and Technology
Series Editor: David J. Lockwood

Ligia Maria Moretto
Kurt Kalcher Editors

Environmental
Analysis by
Electrochemical
Sensors and
Biosensors
Volume 1: Fundamentals

Tai Lieu Chat Luong


Nanostructure Science and Technology
Series Editor:
David J. Lockwood, FRSC
National Research Council of Canada
Ottawa, Ontario, Canada

More information about this series at />


Ligia Maria Moretto • Kurt Kalcher
Editors

Environmental Analysis
by Electrochemical
Sensors and Biosensors

Fundamentals
Volume 1


Editors
Ligia Maria Moretto
Department of Molecular Sciences
and Nanosystems
University Ca’ Foscari of Venice
Venice, Italy

Kurt Kalcher
Institute of Chemistry
Karl-Franzens Universitaăt
Graz, Austria

ISSN 1571-5744
ISSN 2197-7976 (electronic)
ISBN 978-1-4939-0675-8
ISBN 978-1-4939-0676-5 (eBook)
DOI 10.1007/978-1-4939-0676-5
Springer New York Heidelberg Dordrecht London
Library of Congress Control Number: 2014949384
© Springer Science+Business Media New York 2014
This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part
of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations,
recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or
information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar
methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts
in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being

entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication
of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the
Publisher’s location, in its current version, and permission for use must always be obtained from
Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center.
Violations are liable to prosecution under the respective Copyright Law.
The use of general descriptive names, registered names, trademarks, service marks, etc. in this
publication does not imply, even in the absence of a specific statement, that such names are exempt
from the relevant protective laws and regulations and therefore free for general use.
While the advice and information in this book are believed to be true and accurate at the date of
publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for
any errors or omissions that may be made. The publisher makes no warranty, express or implied, with
respect to the material contained herein.
Printed on acid-free paper
Springer is part of Springer Science+Business Media (www.springer.com)


Foreword

Electrochemical sensors are transforming our lives. From smoke detectors in our
homes and workplaces to handheld self-care glucose meters these devices can offer
sensitive, selective, reliable, and often cheap measurements for an ever increasing
diversity of sensing requirements. The detection and monitoring of environmental
analytes is a particularly important and demanding area in which electrochemical
sensors and biosensors find growing deployment and where new sensing opportunities and challenges are constantly emerging.
This manual provides up-to-date and highly authoritative overviews of electrochemical sensors and biosensors as applied to environmental targets. The book
surveys the entire field of such sensors and covers not only the principles of their
design but their practical implementation and application. Of particular value is the
organizational structure. The later chapters cover the full range of environmental
analytes ensuring the book will be invaluable to environmental scientists as well as
analytical chemists.

I predict the book will have a major impact in the area of environmental analysis
by highlighting the strengths of existing sensor technology whilst at the same time
stimulating further research.
Oxford University
Oxford, UK

Richard G. Compton

v



Preface

Dear Reader,
We are pleased that you have decided to use Environmental Analysis by Electrochemical Sensors and Biosensors either as a monograph or as a handbook for your
scientific work. The manual comprises two volumes and represents an overview of
an intersection of two scientific areas of essential importance: environmental
chemistry and electrochemical sensing.
Since the invention of the glass electrode in 1906 by Max Cremer, electrochemical sensors represent the oldest type of chemical sensor and are ubiquitously
present in all chemical labs, industries, as well as in many fields of our everyday
life. The development of electrochemical sensors exploiting new measuring technologies makes them useful for chemical analysis and characterization of analytes
in practically all physical phases - gases, liquids and solids - and in different
matrices in industrial, food, biomedical, and enviromental fields. They have
become indispensible tools in analytical chemistry for reliable, precise, and inexpensive determination of many compounds, as single shot, repetitive, continuous,
or even permanent analytical devices. Environmental analytical chemistry demands
highly sensitive, robust, and reliable sensors, able to give fast responses even for
analysis in the field and in real time, a requirement which can be fulfilled in many
cases only by electrochemical sensing elements.
The idea for this manual was brought to us by Springer. The intention was to

build up an introduction and a concise but exhaustive description of the state of the
art in scientific and practical work on environmental analysis, focused on electrochemical sensors.
To manage the enormous extent of the topic, the manual is split into two
volumes. The first one, covering the basic concepts and fundamentals of both
environmental analysis and electrochemcial sensors,
1. gives a short introduction and description of all environments which are subject
to monitoring by electrochemical sensors, including extraterrestrial ones, as a
particularly interesting and exciting topic;
vii


viii

Preface

2. provides essential background information on electroanalytical techniques and
fundamental as well as advanced sensor technology;
3. supplies numerous examples of applications along with the concepts and strategies of environmental analysis in all the various spheres of the environment and
with the principles and strategies of electrochemical sensor design.
The second volume is more focused on practical applications, mostly complementary to the examples given in volume I, and
1. overviews and critically comments on sensors proposed for the determination of
inorganic and organic analytes and pollutants, including emerging contaminants,
as well as for the measurement of global parameters of environmental
importance;
2. reviews briefly the mathematical background of data evaluation.
We hope that we have succeeded in fulfilling all these objectives by supplying
general and specific data as well as thorough background knowledge to make
Environmental Analysis with Electrochemical Sensors and Biosensors more than
a simple handbook but, rather, a desk reference manual.
It is obvious that a compilation of chapters dealing with so many different

specialized areas in analytical and environmental chemistry requires the expertise
of many scientists. Therefore, in the first place we would like to thank all the
contributors to this book for all the time and effort spent in compiling and critically
commenting on research, and the data and conclusions derived from it.
Of course, we would like to particularly acknowledge all the people from
Springer who have been involved with the process of publication. Our cordial
thanks are addressed to Kenneth Howell, who accompanied us during all the
primary steps and, later during the process of revision and editing together with
Abira Sengupta, was always available and supportive in the most professional and
pleasant manner.
Furthermore, we are indebted to a number of our collaborators, colleagues, and
friends for kindly providing us literature and ideas, and stimulating us with fruitful
discussions. We would also like to thank all the coworkers who did research
together with us and under our supervision, as well as all the scientific community
working in the field of environmental sensing.
In particular, we would like to express our gratitude to all the persons, especially
to our families, who supported us in the period of the preparation of the book.
Last but not least, we will be glad for comments from readers and others
interested in this book, since we are aware that some contributions or useful details
may have escaped our attention. Such feedback is always welcome and will also be
reflected in our future work.
Venice, Italy
Graz, Austria
December 2013

Ligia Maria Moretto
Kurt Kalcher


About the Editors

Ligia Maria Moretto graduated in Chemical Engineering at the Federal University of Rio Grande do Sul, Brazil, and received her Ph.D. in 1994 from the
University Ca’ Foscari of Venice with a thesis entitled “Ion-exchange voltammetry
for the determination of copper and mercury. Application to seawater.” Her academic career began at the University of Caxias do Sul, Brazil, and continued at the
Research Institute of Nuclear Energy, Sao Paulo, Brazil. In 1996 she completed the
habilitation as researcher in analytical chemistry at the University Ca’ Foscari of
Venice. Working at the Laboratory of Electrochemical Sensors, her research field
has been the development of electrochemical sensor and biosensors based on
modified electrodes, the study of gold arrays and ensembles of nanoelectrodes,
with particular attention to environmental applications. She has published more
than 60 papers, several book chapters, and has presented about 90 contributions at
international conferences, resulting in more than 1,100 citations. Prof. Moretto
collaborates as invited professor and invited researcher with several institutions in
Brazil, France, Argentina, Canada, and the USA.
Kurt Kalcher completed his studies at the Karl-Franzens University (KFU) with a
dissertation in inorganic chemistry entitled “Contributions to the Chemistry of
Cyantrichloride, CINCCI2”; he also received his Ph.D. in 1980 from the same
institution. In 1981 he then did postdoctoral work at the Nuclear Research Center
in Juălich (Germany) under the supervision of Prof. Nuărnberg and Dr. Valenta, and
conducted intensive electroanalytical research while he was there. Prof. Kalcher
continued his academic career at KFU with his habilitation on chemically modified
carbon paste electrodes in analytical chemistry in 1988. Since then, he has
been employed there as an associate professor. His research interests include the
development of electrochemical sensors and biosensors for the determination of
inorganic and biological analytes on the basis of carbon paste, screen-printed carbon,

ix


x

About the Editors

and boron-doped diamond electrodes, as well as design, automation, and data handling with small analytical devices using microprocessors. He has published around
200 papers and has presented about 200 contributions at international conferences.
These activities have resulted in more than 3,100 citations. Prof. Kalcher has
received numerous guest professor position offers in Bosnia-Herzegovina, Poland,
Slovenia, and Thailand.


Contents of Volume 1

Part I

Environmental Analysis

1

Introduction to Electroanalysis of Environmental Samples . . . . .
Ivan Sˇvancara and Kurt Kalcher

3

2

Soil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Kenneth A. Sudduth, Hak-Jin Kim, and Peter P. Motavalli

23

3

Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Eduardo Pinilla Gil

63

4

Atmosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Andrea Gambaro, Elena Gregoris, and Carlo Barbante

93

5

Biosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Adela Maghear and Robert Sa˘ndulescu

105

6

Extraterrestrial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Kyle M. McElhoney, Glen D. O’Neil, and Samuel P. Kounaves

131

Part II

Fundamental Concepts of Sensors and Biosensors

7

Electrochemical Sensor and Biosensors . . . . . . . . . . . . . . . . . . . .
Cecilia Cristea, Veronica Haˆrceaga˘, and Robert Sa˘ndulescu

155

8

Electrochemical Sensors in Environmental Analysis . . . . . . . . . .
Cecilia Cristea, Bogdan Feier, and Robert Sandulescu

167

9

Potentiometric Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Eric Bakker

193

10

Controlled Potential Techniques in Amperometric Sensing . . . . . .
Ligia Maria Moretto and R. Seeber

239

xi


xii

Contents of Volume 1

11

Biosensors on Enzymes, Tissues, and Cells . . . . . . . . . . . . . . . . . .
Xuefei Guo, Julia Kuhlmann, and William R. Heineman

283

12

DNA Biosensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filiz Kuralay and Arzum Erdem

313

13

Immunosensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Petr Skla´dal

331

14

Other Types of Sensors: Impedance-Based Sensors,
FET Sensors, Acoustic Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . .
Christopher Brett

Part III
15

351

Sensor Electrodes and Practical Concepts

From Macroelectrodes to Microelectrodes: Theory
and Electrode Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Salvatore Daniele and Carlo Bragato

373

16

Electrode Materials (Bulk Materials and Modification) . . . . . . . . .
Alain Walcarius, Mathieu Etienne, Gre´goire Herzog,
Veronika Urbanova, and Neus Vila

403

17

Nanosized Materials in Amperometric Sensors . . . . . . . . . . . . . . .
Fabio Terzi and Chiara Zanardi

497

18

Electrochemical Sensors: Practical Approaches . . . . . . . . . . . . . .
Anchalee Samphao and Kurt Kalcher

529

19

Gas Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ulrich Guth, Wilfried Vonau, and Wolfram Oelßner

569

Part IV

Sensors with Advanced Concepts

20

Sensor Arrays: Arrays of Micro- and Nanoelectrodes . . . . . . . . . .
Michael Ongaro and Paolo Ugo

583

21

Sensors and Lab-on-a-Chip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Alberto Escarpa and Miguel A. Lo´pez

615

22

Electronic Noses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Corrado Di Natale

651

23

Remote Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tomer Noyhouzer and Daniel Mandler

667

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

691


Contents of Volume 2

Part I

Sensors for Measurement of Global Parameters

1

Chemical Oxygen Demand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Usman Latif and Franz L. Dickert

719

2

Biochemical Oxygen Demand (BOD) . . . . . . . . . . . . . . . . . . . . . .
Usman Latif and Franz L. Dickert

729

3

Dissolved Oxygen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Usman Latif and Franz L. Dickert

735

4

pH Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Usman Latif and Franz L. Dickert

751

Part II

Sensors and Biosensors for Inorganic Compounds

of Environmental Importance

5

Metals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ivan Sˇvancara and Zuzana Navra´tilova´

781

6

Non-metal Inorganic Ions and Molecules . . . . . . . . . . . . . . . . . . .
Ivan Sˇvancara and Zuzana Navra´tilova´

827

7

Electroanalysis and Chemical Speciation . . . . . . . . . . . . . . . . . . .
Zuzana Navra´tilova´ and Ivan Sˇvancara

841

8

Nanoparticle-Emerging Contaminants . . . . . . . . . . . . . . . . . . . . .
Emma J.E. Stuart and Richard G. Compton

855

xiii


xiv

Contents of Volume 2

Part III

Sensors and Biosensors for Organic Compounds
of Environmental Importance

9

Pharmaceuticals and Personal Care Products . . . . . . . . . . . . . . .
Lu´cio Angnes

881

10

Surfactants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Elmorsy Khaled and Hassan Y. Aboul-Enein

905

11

Determination of Aromatic Hydrocarbons
and Their Derivatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

K. Peckova-Schwarzova, J. Zima, and J. Barek

931

12

Explosives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jiri Barek, Jan Fischer, and Joseph Wang

965

13

Pesticides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Elmorsy Khaled and Hassan Y. Aboul-Enein

981

Part IV

Electrochemical Sensors for Gases of Environmental
Importance

14

Volatile Organic Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1023
Tapan Sarkar and Ashok Mulchandani

15

Sulphur Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1047
Tjarda J. Roberts

16

Nitrogen Compounds: Ammonia, Amines and NOx . . . . . . . . . . . . 1069
Jonathan P. Metters and Craig E. Banks

17

Carbon Oxides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1111
Nobuhito Imanaka and Shinji Tamura

Part V
18

Data Treatment of Electrochemical Sensors and Biosensors

Data Treatment of Electrochemical Sensors and Biosensors . . . . . 1137
Elio Desimoni and Barbara Brunetti

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1153


Part I

Environmental Analysis


Chapter 1

Introduction to Electroanalysis
of Environmental Samples
Ivan Sˇvancara and Kurt Kalcher

1.1

Electroanalysis

For lengthy decades, electroanalysis represents the largest area of applied
electrochemistry, involving measurements of the electric signals associated with
the behaviour and/or transformations of charged species in the solution. From
traditional point of view, electroanalysis can be classified as a special area of
electrochemistry which is primarily focused on the determination (quantification)
of chemical substance(s) in a sample, but also on qualitative characterisation—i.e.,
identification.
Historically, one can find the first pioneering attempts with potentiostatic electrolysis/electrogravimetry that can be considered as analytical applications within
some revolutionary electrochemical experiments (see examples in reference (1));
nevertheless, real electroanalysis began in the first half of the twentieth century with
the development of potentiometric and amperometric analytical methods characterized by milestones such as design and physicochemical interpretation of the first
real electrochemical sensor, the glass electrode by Cremer and Haber2,3 and
Heyrovsky´’s invention of polarography.4,5 The latter had launched a tremendous
development of techniques with modulated potential ramps,6–8 followed by invention of the highly effective electrochemical stripping analysis9,10 and its further
extension to the time-dependent potentiometric mode.11 A wide application of the
methods to environmental, pharmaceutical, and medical analyses resulted
I. Sˇvancara (*)
Department of Analytical Chemistry, Faculty of Chemical Technology,
University of Pardubice, CZ-532 10, Pardubice, Czech Republic
e-mail:
K. Kalcher

Institute of Chemistry—Analytical Chemistry, Karl-Franzens-University of Graz,
Universitaetsplatz 1, 3000, Graz, Austria
e-mail:
© Springer Science+Business Media New York 2014
L.M. Moretto, K. Kalcher (eds.), Environmental Analysis by Electrochemical
Sensors and Biosensors, DOI 10.1007/978-1-4939-0676-5_1

3


4

I. Sˇvancara and K. Kalcher

accompanied by coupling electroanalytical devices to flow systems (amperometric
or coulometric detection)12,13 that contributed to the expansion of electrochemical
principles into the realm of analytical separations.
In parallel with these current flow-based measurements (equilibrium)
potentiometry held an important position,14 particularly after introduction of all
the various types of ion-sensitive membranes whereas conductometry,
oscillometry, and dielectrometry15 were an occasional choice and nearly the same
can be said about some other measurements (e.g. biamperometry and
bipotentiometry,16 chronoamperometry and chronopotentiometry17). In the last
half century, other techniques were proposed, such as sonovoltammetry,18 electrochemical impedance spectroscopy (EIS19), electrochemiluminescence,20
spectroelectrochemistry,21 and scanning electrochemical microscopy (SECM22).
Similar to other fields of instrumental analysis, the development and expansion
of both electrochemistry and electroanalysis is tightly associated with the progress
in instrumentation; some apparatuses over the years are depicted in Fig. 1.1. The
first automated electroanalytical analyzer, a polarograph constructed by Heyrovsky
and Shikata,24 was practically also the first automatic analytical device at all. With

the rapid technical development after the WW II, various devices had appeared on
the market which allowed comfortable voltammetric and potentiometric analyses
with a high degree of automatization; companies worth to mention in this context
are Tacussel in France, Princeton Applied Research (PAR, later part of EG&G) and
Orion in the US, Metrohm in Switzerland and Radiometer in Denmark (see
Fig. 1.1c). The first commercial whole blood glucose analyzer was introduced in
the US by Yellow Springs Instruments in 1975, it was the legendary Yellow Springs
Glucose Analyzer Model 23A based on the first biosensor developed by Leland
“Lee” Clark.25 Nowadays there is the trend for miniaturisation on one hand, as
demonstrated by hand-held devices produced by PalmSens or DropSens; on the
other we find sophisticated desktop instruments offering the whole landscape of
electrochemical techniques such as AutoLab (Metrohm) or BASi (Bioanalytical
Systems Inc.) analyzers.
With respect to electrodes potentiometry started with the glass electrode from
Cremer in 1906 2; starting in the 1960s the development of polymer-based membranes had a strong impact on the popularity of ion-sensitive electrodes.
Mercury was the dominant electrode material for current-based measurements in
the first half of the twentieth century, which has eventually changed during its
second half ending up in some kind of mercuryphobia. Nevertheless, other materials came to the fore as a consequence, such as graphite, glassy carbon, gold plus
some other precious metals, and newly also bismuth.
A milestone was the invention of carbon paste by Ralph “Buzz” Adams in
1958,26 which favoured, due to its heterogeneous paste-like composition, simple
and multiple modification of the electrode material even with labile biological
components. The first amperometric sensor, the famous “Clark oxygen electrode”
was described in by Leland Clark 1954.27 Currently, new substances have a primary
position in electrochemical literature, such as boron-doped diamond or nanostructured materials.


1 Introduction to Electroanalysis of Environmental Samples

5

Fig. 1.1 Potentiostat: Original polarographic analyzer by Heyrovsky´ (a); Princeton Applied
Research Model 164 (b); Radiometer TraceLab PSU unit with the electrode stand (c); AutoLab
Model PSTAT (d); handheld device PalmSens (e). Photo (a) reproduced from reference (23) with
permission of Prof. Z. Samec, Heyrovsky Institute, Prague, Czech Republic, photos (b–e) by the
authors (K. Kalcher and I. Sˇvancara)

1.2

A Glance into Electroanalytical Literature

The extent of electrochemical literature, apart from publications in scientific journals,
is very wide, meaning that any surveys or suggestions to be made are always arbitrary
and incomplete. Within such a selection,5,13,16,19,21,22,28–66 one can find extensive book
series,37,40,49 chapters in encyclopedic literature (e.g. reference (33)), fundamental and
general textbooks (e.g. references (5, 29, 35, 46–48, 53)), practical guides,38–41,52,54
and monographs focused on instrumentation,44,45 electrodes,5,32,66 analyses41,55,58 and
techniques,13,16,39,43,51 including new disciplines11,19,22. Whereas most of books
listed still are available worldwide (e.g. references (29, 35, 45, 66)), other issues and
releases have more regional or local character.56–65


I. Sˇvancara and K. Kalcher

6

1.3

Electroanalysis in a Flash

As each field of instrumental analysis, also electrochemical measurements can be
evaluated via the respective possibilities and limitations, without need of going into
specific details.

1.3.1
–
–
–
–
–

–
–
–
–
–
–
–

–
–

Advantages

Long tradition and highly elaborated theoretical background.
Relatively simple and inexpensive instrumentation.
Generally low investment and operational costs.
High level of diversity in modifying the instrumentation (including electrodes)
for special purposes.
Wide flexibility in practical analysis (of inorganic ions, complexes and molecules, organic substances as well as biologically important compounds, including some microorganisms).

Excellent performance in trace analysis (high selectivity, extraordinary detection characteristics).
Applicability in speciation and differentiation analysis.
Suitable as reference technique/method in evaluations of new procedures for
routine analysis.
Adaptability for field monitoring and similar outdoor employment.
Good premises for miniaturisation and compatibility with PC controlled
systems.
Wide applicability of new technologies.
Good compatibility with other analytical instrumentation (detection in flow
injection analysis (FIA), high performance liquid chromatography (HPLC),
and capillary electrophoresis (CE); combinations with optical and microscopic
techniques).
Adaptability to the principles of green analytical chemistry.
Widely accessible educational tool for training and practicing of young analysts.

1.3.2

Drawbacks

– Relatively high knowledge required to understand principles and techniques, as
well as to interpret data.
– High susceptibility to matrix influences.
– Limited stability of detection/sensing units, requiring frequent (re)calibration.
– Complicated and time-consuming regeneration of some electrodes and
detectors.


1 Introduction to Electroanalysis of Environmental Samples

7

– Wide diversity of electrode materials, modifiers, and detection techniques differing principally in the properties and performance, thus needing certain
orientation.
– Discontinuity of measurement if low detection limits are required (typically, in
stripping analysis with pre-concentration).
– Limited application to multicomponent analyses.
– Frequent use of toxic and harmful materials or reagents.
– Particular need for well-trained operators/users.
Amongst electroanalysts, some points gathered in the above-given Pros & Cons—
and, especially, those described as disadvantages—may induce certain displeasure.
It is quite natural, but the authors of this text have compiled both surveys carefully
and being fully convinced about usefulness of such confrontation. Because even an
incidental polemics about the individual points seems to be beneficial as it would
indicate mainly the liveliness of the field that successfully “struggles for lengthy
decades” with other instrumental techniques.

1.4
1.4.1

Electrochemistry and Environmental Analysis
History and Present

First environmental focused analyses can surely be found already within the early
era of electrochemical measurements (see references (29, 38–40, 43) and references
therein); nevertheless, a more systematic orientation towards the environmental
samples began later, in the early 1970s of the twentieth century. In this context, the
most renowned groups (or even schools) were the teams of H.W. Nuărnberg and
P. Valenta in Juelich (Germany) and M. Branica in Zagreb (Croatia). Later S. Van
den Berg’s group in Great Britain performed extensive—and, in overall scope,
unprecedented—marine environmental research, resulting, among others, in a wide

palette of ultimate methods for the determination of various metals and metallic
species in sea water (e.g., references (67–69) and references therein).
Of similar focus was the scientific interest of the Australian electrochemist
T.M. Florence,70 also known as the inventor of the in-situ plated mercury film
electrode, MFE,71 and of his successor, A.M. Bond.72,73 In the U.S., the use of
stripping voltammetry in environmental analysis and modern trends in electrochemical instrumentation as such were widely popularised by Joseph “Joe”
Wang74–76 whose legendary monograph from the mid-1980s28 still belongs
amongst the top texts in the field. Traditionally strong electrochemistry in the
former U.S.S.R also included some scientists active in environmental analysis,
such as Kh. Z. Braininas group.77,78
In Europe, H.W. Nuărnberg79,80 had, together with M. Stoeppler,81 promoted the
establishment of a special multidisciplinary project, the “Environmental Specimen
Bank (ESB)”. Logistically and materially, the ESB program was realised in Juelich


8

I. Sˇvancara and K. Kalcher

Fig. 1.2 Institute of Applied Physical Chemistry, the Reseach Centre Juelich, in the mid-1990s:
Environmental Specimen Bank (E.S.B.) in the front, research labs and offices in the back [photo by
the author (I. Svancara)]

(Nord-Rhine Westphalia; see also Fig. 1.2) as a systematic collection of representative environmental samples, their long-time storage (for future generations), and
regular control analyses with the aid of AAS, neutron activation analysis, isotope
dilution-mass spectrometry, ion chromatography, and electrochemical techniques.
Stripping analysis was used to determine selected metals and metalloids;
namely: Zn, Cd, Pb, Cu, Tl, Ni, Co, As, and Se, by employing ASV, AdSV, PSA,
or CCSA (see references (82, 83) and references therein).
Nowadays, globally seen, many scientific teams and individuals focus research

on environmental analysis, such as in western,84–99 southern,100–104 northern11,98
and middle Europe including countries of former Yugoslavia. 33,51,105–116 In North
America, notable activities can be seen across the U.S.A., opening a number of new
attractive applications, thanks to a wide employment of chemically modified
electrodes,74,75,117 special flow systems for air analysis (e.g. reference (118)), or
decentralised monitoring with portable analysers.119–122 Interesting applications
can be traced up in Latin America; just to pick out a few of the many examples:
determination of electrochemically inert Li+ ions,123 highly sensitive detection of
HgII at a gold layer-based detector made of a recordable compact disc,124 or unusual
electroanalysis of non-aqueous samples of crude oil.125
Also in Africa, some representatives are involved in environmental analysis,126,127 and the same can be said about the Near128–130 and the Far East,131–138


1 Introduction to Electroanalysis of Environmental Samples

9

where the leading position is naturally held by highly populated China (see
e.g. reference (131) and references therein).

1.4.2

Main Topics

Undoubtedly, a discipline that includes the identification, quantification, and monitoring of various species in the environment is also one of the largest areas of
electroanalysis (see e.g. references (28, 58, 67–83, 99, 119–122, 131, 139–176))
The key topics in environmental analysis and therefore also in electrochemical
environmental analysis as can be seen by corresponding review articles in the
literature are, apart from certain necessities, also subject to trends and collective
behaviours (see e.g. references (68, 70, 75, 77, 81, 140–146) and references

therein). In the following survey the most important analytes are summarised:
– Toxic heavy metals (mainly Cd, Pb, Cu, and Hg); usually at very low concentration levels and determined by methods of trace analysis, occasionally also
with the aid of speciation analysis (e.g.: Cu2+ and [Cu(OH)m](mn), Hg2+ and
[HgClm](mn) or HgII and Hg-CH3+).
– Metals of strategic importance (Co, Ni, V, Mn, Cr, Mo, U); in wide concentration ranges, often, in complex matrices of waste waters or originally solid
materials; studied due to the occurrence at different valence (CoII vs. CoIII,
MnII vs. MnVII, CrIII vs. CrVI etc.).
– Highly toxic metals with less common occurrence (Tl, In, Ge, Be); monitored
mainly in heavily polluted industrial localities.
– Other metals frequently occurring in the environment (Fe, Al, Zn); in many
cases, studied via chemical speciation in aquatic systems (as hydrated ions [Me
(OH)m](mn)).
– Less common metals (Sb, Bi, Ti, Nb, Ta, and some rare earths of the Sc and Ac
groups); known as minor components of various electronics and industrial
catalysts.
– Precious metals (Au, Ag); the latter gaining a considerable attention in its new
nanoforms applicable as effective disinfectants151.
– Platinum metals (Ru, Rh, Pd, Os, Ir, Pt); a family of catalytically acting species
whose impact on the environment is not yet fully understood; see introduction
in reference (152) and the next section.
– Organometallic compounds containing Hg, Pb, Sn, and Bi; all occurring as both
naturally and industrially released species.
– Metalloids (As and Se); often as the subjects of interest in speciation analysis
(AsV, AsIII, AsIII, and AsORG or SeIV and SeVI, respectively).
– Toxic and harmful anions, such as nitrogen-based ions (NO2, NO3, N3,
NH4+, and N2H5+), sulphur anions (SO42, SO32, S2), phosphates (HPO42,
[PO3]x, PORG); all being applied as fertilizers, industrial explosives, food additives, conserving or water-treatment agents.


10

I. Sˇvancara and K. Kalcher

– Gases in air and dissolved in aquatic systems (O2, CO2, NH3) and gaseous
emissions from volcanoes, industry, cars, and firing processes (NOX, SO2, Cl2,
HCHO, etc.).
– Organic pollutants; namely: polyaromatic hydrocarbons (PAHs) with their NO2and NH2-derivatives, nitroso-amines, and similar potentially carcinogenic compounds, herbicides and pesticides (halogenated aromates, organophosphates,
carbamides) and related formulations for agricultural use, synthetic dyes, or
industrially applied surfactants.
– Biologically important compounds; e.g., compounds of fluorine and iodine,
biogenic amines, some antioxidants or plasticizers (e.g. phthalates).
Electrochemical analyses can often be specifically tailored for special applications or uncommon matrices, such as quantification of selected metals in crude oil
and petroleum,125 analysis of industrial plating baths (see e.g. references (146,
147)), or physical characterisation and elemental analysis of solid minerals and
rocks.52,148 Among organic and biological compounds that have attracted attention
of environmental analysts in the recent years (see e.g. reference (150)), one can
name explosives in soil,177 newly defined groups of persistent organic pollutants
(POPs), including some new types of pesticides, volatile organic compounds
(VOCs), cytokinine-based plant hormones or cyanotoxins.153 Some other “new
analytes” of interest have come forth in environmental electroanalysis; mostly,
associated with the dynamic progress of new technologies and modern communication systems.33,120,149,150,178
During the last four decades, the objectives of environmental electroanalysis
have changed significantly. Whereas at the beginning the determination of (total)
elements as a laboratory method was in the foreground, this position is now held by
very potent multielement techniques, to mention in the first place inductivelycoupled plasma mass spectrometry (ICP-MS) which is also gradually replacing
less efficient methods, such as atomic absorption spectrometry (AAS). Nevertheless, electrochemical analysis still maintains a niche if its strengths are exploited to
its advantage: as a sensing device. The instruments can be made small and mobile,
so sensing of elements directly in the field at the point of interest may result in very
cost-effective strategies if decisions can be made ad hoc if a sample should be sent
to the laboratory for further analysis or if concentrations of noxious substances are

below a threshold not worth of further analysis.
Thus, the main strength of electroanalysis is not elemental analysis, but determination of various species, organic and inorganic compounds of toxicological,
environmental, and biological importance. The real future of electroanalysis is
sensing and detecting compounds which is with other methods difficult to achieve,
expensive or labour-intensive. As can be seen with the current literature already,
biosensors in all forms, but also other types of special or even specific detectors will
be in the central focus of research.
Environmental analysis and electroanalysis of the new millennium reflect also
some further trends. At first, there is still a growing influence of green chemistry,
resulting soon in the establishment of a new discipline, green analytical


1 Introduction to Electroanalysis of Environmental Samples

11

chemistry.119,154 In close association with the strictly ecological principles, the
2000s saw the rise of “mercuryphobia”,155 which is a phenomenon covering a
more intense monitoring of mercury(II) compounds in the environment and, mainly,
culminating in aversion against the use of liquid mercury-based electrodes, including traditional configurations of the HMDE, DME, and MFE. It is indisputable that
the electroanalysts may miss these highly reliable and flexible detection tools, on the
other hand, the respective efforts to find alternate electrode materials have already
led to the notable achievements beneficial also for environmental analysis. Herein,
one has to quote the invention and a rapid expansion of bismuth-based electrodes
and related sensors156,179 that have been shown to be almost comparable substitutes
for the mercury counterparts in many applications while remaining environmentally
friendly or, at least, markedly less toxic than mercury and its compounds.

1.4.3

Sampling, Sample Storage, and Pretreatment

Sampling is one of the most crucial points in environmental analytical chemistry.
Most mistakes made in this phase cannot be eliminated by the analytical method
anymore. The main objectives are to avoid contamination on one hand, and loss of
analytes on the other.
Gases can be sampled by standardised procedures and apparatuses; gases themselves can be absorbed in liquids or adsorbed on solid tube-like supports. Particulate
matter in gases is precipitated either as a whole in electrofilters or other types of
precipitators, or can be fragmented according to particle sizes by cascade impactors.
Liquids/Solutions (mainly various types of water) have to be carefully sampled
to avoid contamination; e.g., early analyses of lead in ocean water showed too high
results because of contamination of sea water from the boat itself. Water samples
are usually filtered through membranes with 0.45 or 0.2 μm pore size to separate
liquid and particulate matter. Waters from greater depths are sampled with special
deep water sampling devices.
Soils from surfaces are sampled according to the specific top layers; they are usually
rather inhomogeneous and often separated into different components (roots, larger
stones etc.), homogenised and sieved. Soils from deeper layers are obtained by drilling,
where contamination by abrasion of the driller should be observed.
Biological samples may show strong individual variations of analytes due to
different dispositions and exposition conditions; apart from this it must be taken
into account that organs and even sub-structures of organs can vary strongly in their
composition. Such factors must be considered during sampling already. Animal and
plant tissues and fluids may suffer from metal contamination when being in contact
with metallic instruments; special cutting and operational tools are avail (e.g., from
quartz glass or pure titanium).
Storage is a crucial aspect for many samples, particularly when the analytes are
present at trace concentrations. The storage container materials must be chosen
carefully because they may be permeable for ions, gasses, and water; but also the