The combination of aptamers with its high selectivity and specificity and EIS
also merges their advantages. Thus, impedimetric aptasensors have high potential in
biotechnology, e.g., in screenings, bioprocess monitoring, and quality inspection.
The first impedimetric aptasensor was described by Rodriguez et al. [1] in
2005 for the detection of lysozyme. Only 2 months later, Xu et al. [2] reported
an impedance sensor using aptamers to detect the human immunoglobulin E. Since
then, the number of publications on impedimetric biosensors increased continuously
every year (see Fig. 1). To date, there are impedimetric aptasensors for ~85 different
targets, including potassium ions, small molecules (e.g., adenosine), proteins, and
whole cells.
There are several excellent reviews about electrochemical aptasensors, as, for
example, by de-los-Santos-Álvarez et al. [3] who summarize the state of the art in
label-free detection strategies for aptamer-ligand interaction. The book Aptamers in
Bioanalysis by Mascini [4] contains a good selection of aptamer applications
in biosensors, whereas the reviews by Hianik and Wang and Sassolas et al. [5, 6]
concentrate on electrochemical detection strategies for aptasensors. The more
recent review by Ferapontova and Gothelf [7] concentrates on the advances made
in electrochemical aptasensors especially those based on conformational detection
strategies and nanotechnology. The book chapter by Li and Ellington [8] describes
electrochemical techniques for aptasensors divided into label-free and label-based
detection strategies. The short review by Chiorcea-Paquim and Oliveira-Brett [9]
specializes on G-quadruplex-based electrochemical biosensors. The most recent
review by Muñoz et al. [10] is about impedimetric biosensors and contains a short
paragraph about aptasensors.
This book chapter reviews the advances in impedimetric measurement techniques
of aptasensors since 2005. Section 2 describes the basics of impedimetric measurement techniques with emphasis on different signal shapes. Since there are several
reviews about detection strategies developed for impedimetric biosensors, only new
developments in detection strategies in the last years will be discussed in Sect. 3
divided into non-faradaic and faradaic measurement cells. And the last section
Fig. 1 Trend in number of publications on impedimetric biosensors in general (gray) and
aptamer-based impedimetric biosensors (dark gray) in the last decade (searched with PubMed
(all databases), Web of Science (TIB Hanover), ScienceDirect, and Springer)
Impedimetric Aptamer-Based Biosensors: Principles and Techniques
19
also merges their advantages. Thus, impedimetric aptasensors have high potential in
biotechnology, e.g., in screenings, bioprocess monitoring, and quality inspection.
The first impedimetric aptasensor was described by Rodriguez et al. [1] in
2005 for the detection of lysozyme. Only 2 months later, Xu et al. [2] reported
an impedance sensor using aptamers to detect the human immunoglobulin E. Since
then, the number of publications on impedimetric biosensors increased continuously
every year (see Fig. 1). To date, there are impedimetric aptasensors for ~85 different
targets, including potassium ions, small molecules (e.g., adenosine), proteins, and
whole cells.
There are several excellent reviews about electrochemical aptasensors, as, for
example, by de-los-Santos-Álvarez et al. [3] who summarize the state of the art in
label-free detection strategies for aptamer-ligand interaction. The book Aptamers in
Bioanalysis by Mascini [4] contains a good selection of aptamer applications
in biosensors, whereas the reviews by Hianik and Wang and Sassolas et al. [5, 6]
concentrate on electrochemical detection strategies for aptasensors. The more
recent review by Ferapontova and Gothelf [7] concentrates on the advances made
in electrochemical aptasensors especially those based on conformational detection
strategies and nanotechnology. The book chapter by Li and Ellington [8] describes
electrochemical techniques for aptasensors divided into label-free and label-based
detection strategies. The short review by Chiorcea-Paquim and Oliveira-Brett [9]
specializes on G-quadruplex-based electrochemical biosensors. The most recent
review by Muñoz et al. [10] is about impedimetric biosensors and contains a short
paragraph about aptasensors.
This book chapter reviews the advances in impedimetric measurement techniques
of aptasensors since 2005. Section 2 describes the basics of impedimetric measurement techniques with emphasis on different signal shapes. Since there are several
reviews about detection strategies developed for impedimetric biosensors, only new
developments in detection strategies in the last years will be discussed in Sect. 3
divided into non-faradaic and faradaic measurement cells. And the last section
Fig. 1 Trend in number of publications on impedimetric biosensors in general (gray) and
aptamer-based impedimetric biosensors (dark gray) in the last decade (searched with PubMed
(all databases), Web of Science (TIB Hanover), ScienceDirect, and Springer)
Impedimetric Aptamer-Based Biosensors: Principles and Techniques
19