1 Introduction
The main focus of this book chapter is on the review of impedimetric aptasensors
since 2005 for their possible applications in biotechnology, in particular in the fields
of health care, food inspection, and environmental protection (Sects. 2–4) with
emphasis on target type, limit of detection, and real sample testing. Their performance will be compared to other biosensors to discuss, which benefits they offer and
which challenges still have to be taken for their introduction into market (Sect. 5).
Although several academic databases and search engines were sifted, some articles
might have been overlooked.
2 Impedimetric Aptasensors for Health Care Applications
(Red Biotechnology)
Red biotechnology aims to advance the application of biotechnological tools to
benefit (bio)medical purposes. Besides developing and providing drugs, a major
purpose of red biotechnology addresses the field of medical diagnostics. Instrumental diagnostic procedures are necessary in order to derive reliable diagnoses and
thereby specific therapy decisions. With regard to red biotechnology, the analysis of
usually complex samples (e.g. whole blood) often requires multiple processing steps
in standard laboratories which demand time, highly trained personnel, and money.
An ideal sensor offers cost-efficient, selective, and rapid measurements of
non-processed as well as low-volume samples. Point-of-care tests point toward
such specifications and enable rapid detection of analytes on-site, which can be
crucial depending on the specific disease as well as the medical supply available to
the patient. Readouts of point-of-care tests by smartphone applications might be the
highlight of the development of simplified analysis and exchange of information
with even distant professionals. The crucial question is if impedimetric aptasensors
match these requirements.
Impedimetric aptasensors combine the advantages of aptamers with the advantages of EIS (electrochemical impedance spectroscopy). EIS-based sensors are
promising with regard to simplified diagnostics due to rapid and label-free application without complex sample preparation. Based on the sensitivity of impedance
changes at the interface of electrode and electrolyte, even the detection of analytes in
the pM range is feasible. The selectivity of the sensor is ensured by aptamers which
are short, stable and cost-efficient molecules [1–3].
This paragraph reviews recent publications in the field of aptamer-based
impedimetric biosensors targeting medically relevant analytes, grouped by their
application in the diagnosis of diseases, cancer detection, and other use cases. This
review shows the potential of impedimetric aptasensors for detection and analysis of
a variety of targets (e.g. proteins, cells, small molecules) from even complex origin
(e.g. serum, plasma, urine).
Impedimetric Aptamer-Based Biosensors: Applications
45
The main focus of this book chapter is on the review of impedimetric aptasensors
since 2005 for their possible applications in biotechnology, in particular in the fields
of health care, food inspection, and environmental protection (Sects. 2–4) with
emphasis on target type, limit of detection, and real sample testing. Their performance will be compared to other biosensors to discuss, which benefits they offer and
which challenges still have to be taken for their introduction into market (Sect. 5).
Although several academic databases and search engines were sifted, some articles
might have been overlooked.
2 Impedimetric Aptasensors for Health Care Applications
(Red Biotechnology)
Red biotechnology aims to advance the application of biotechnological tools to
benefit (bio)medical purposes. Besides developing and providing drugs, a major
purpose of red biotechnology addresses the field of medical diagnostics. Instrumental diagnostic procedures are necessary in order to derive reliable diagnoses and
thereby specific therapy decisions. With regard to red biotechnology, the analysis of
usually complex samples (e.g. whole blood) often requires multiple processing steps
in standard laboratories which demand time, highly trained personnel, and money.
An ideal sensor offers cost-efficient, selective, and rapid measurements of
non-processed as well as low-volume samples. Point-of-care tests point toward
such specifications and enable rapid detection of analytes on-site, which can be
crucial depending on the specific disease as well as the medical supply available to
the patient. Readouts of point-of-care tests by smartphone applications might be the
highlight of the development of simplified analysis and exchange of information
with even distant professionals. The crucial question is if impedimetric aptasensors
match these requirements.
Impedimetric aptasensors combine the advantages of aptamers with the advantages of EIS (electrochemical impedance spectroscopy). EIS-based sensors are
promising with regard to simplified diagnostics due to rapid and label-free application without complex sample preparation. Based on the sensitivity of impedance
changes at the interface of electrode and electrolyte, even the detection of analytes in
the pM range is feasible. The selectivity of the sensor is ensured by aptamers which
are short, stable and cost-efficient molecules [1–3].
This paragraph reviews recent publications in the field of aptamer-based
impedimetric biosensors targeting medically relevant analytes, grouped by their
application in the diagnosis of diseases, cancer detection, and other use cases. This
review shows the potential of impedimetric aptasensors for detection and analysis of
a variety of targets (e.g. proteins, cells, small molecules) from even complex origin
(e.g. serum, plasma, urine).
Impedimetric Aptamer-Based Biosensors: Applications
45