Nanofluidic redox cycling amplification for the selective detection of catechol.
We have developed a chip-based nanofluidic device to amplify the electrochemical signal of catechols by orders of magnitude. The amplification is based on rapid redox cycling between plane parallel electrodes inside a nanochannel. We show that it is possible to monitor the signal of only a few hundred molecules residing in the active area of the nanofluidic sensor. Furthermore, due to the nanochannel design, the sensor is immune to interference by molecules undergoing irreversible redox reactions. We demonstrate the selectivity of the device by detecting catechol in the presence of ascorbic acid, whose oxidized form is only stable for a short time. The interference of ascorbic acid is usually a challenge in the detection of catecholamines in biological samples.
Wolfrum
Bernhard
B
Kavli Institute of Nanoscience, Section Molecular Biophysics, Technical University Delft, Delft, The Netherlands.
Zevenbergen
Marcel
M
Lemay
Serge
S
D001205:Ascorbic Acid / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D002395:Catecholamines / Q000032:analysis* / Q000737:chemistry; D002396:Catechols / Q000032:analysis* / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D010084:Oxidation-Reduction; D012680:Sensitivity and Specificity; D012834:Silver / Q000737:chemistry; D018030:Silver Compounds / Q000737:chemistry
D002395:Catecholamines; D002396:Catechols; D018030:Silver Compounds; D012834:Silver; C034221:catechol; C037548:silver chloride; D001205:Ascorbic Acid