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Quantum dots on electrodes—new tools for bioelectroanalysis

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Abstract

The review covers recent developments in which quantum dots (QDs) are combined with electrodes for detection of analytes. Special focus will be on the generation of photocurrents and the possibility of spatially resolved, light-directed analysis. Different modes for combining biochemical reactions with QDs will be discussed. Other applications involve the use of QDs as labels in binding analysis. Different methods have been developed for read-out. In addition to photocurrent analysis, voltammetric detection of metals and electrochemiluminescence (ECL) can be used. In the latter, light is the sensor signal. ECL-based systems combine the advantage of very sensitive analytical detection with rather simple instrumentation.

Scheme of an enzymatic signal chain on a quantum dot electrode. Here the detection of glucose is achieved by the conversion of the enzymatically generated NADH at the illuminated QDs

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Abbreviations

AChE:

Acetycholine esterase

ALP:

Alkaline phosphatase

ATP:

Adenosine triphosphate

BDT:

1,4-Dithiobenzene

CCD:

Charge-coupled device

CNTs:

Carbon nanotubes

[Co(Phen)3Cl2]:

Cobalt phenanthroline chloride

CRET:

Chemical resonance energy transfer

Cy5:

Fluorescence dye (for Cy5 Ex = 650 nm; Em = 670 nm)

cyt c:

Cytochrome c

DET:

Direct (heterogeneous) electron transfer

ECL:

Electrochemiluminescence

ERET:

Electrochemical resonance energy transfer

FRET:

Förster resonance energy transfer

GDH:

Glucose dehydrogenase

GOD:

Glucose oxidase

HEPES:

4-(2-Hydroxyethyl)-1-piperazineethanesulfonic acid

HRP:

Horseradish peroxidase

IgG:

Immunoglobulin G

ITO:

Indium tin oxide

LAPS:

Light-addressable potentiometric sensors

LDH:

Lactate dehydrogenase

NAD+/NADH:

Nicotinamide adenine dinucleotide

NPs:

Nanoparticles

NR:

Nitrate reductase

PAH:

Polyallylamine hydrochloride

pAP:

p-Aminophenol

pAPP:

p-Aminophenylphosphate

PSA:

Prostate-specific antigen

QDs:

Quantum dots

[Ru(bpy)3]2+ :

Ruthenium bipyridine complex

TOPO:

Trioctylphosphine oxide

TPrA:

Tri-n-propylamine

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Correspondence to F. Lisdat.

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Published in the topical collection Bioelectroanalysis with guest editors Nicolas Plumeré, Magdalena Gebala, and Wolfgang Schuhmann.

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Lisdat, F., Schäfer, D. & Kapp, A. Quantum dots on electrodes—new tools for bioelectroanalysis. Anal Bioanal Chem 405, 3739–3752 (2013). https://doi.org/10.1007/s00216-013-6789-1

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