MICROCHIP ELECTROPHORESIS-SINGLE WALL CARBON NANOTUBE PRESS-TRANSFERRED ELECTRODES FOR FAST AND RELIABLE ELECTROCHEMICAL SENSING OF MELATONIN AND ITS PRECURSORS

FEDERICO J. V. GOMEZ; AIDA MARTÍN GALAN; MARIA FERNANDA SILVA; ALBERTO ESCARPA

ELECTROPHORESIS

WILEY-V C H VERLAG GMBH

Año: 2015

0173-0835

In the current work, single wall carbon nanotube press-transferred electrodes (SW-PTEs)were used for detection of melatonin (MT) and its precursors tryptophan (Trp) and serotonin (5-HT) on microchip electrophoresis(ME). SW-PTEs were simply fabricated by press transferring a filtered dispersion of single wall carbon nanotubes (SWCNTs) on a non-conductive PMMA substrate, where SWCNTs act asexclusivetransducers.The coupling of ME-SW-PTEs allowed the fast detection ofMT, Trp and 5-HT in less than 150 s with excellent analytical features. It exhibited an impressive anti fouling performance with RSD values of ≤2% and ≤4% for migration times and peak heights, respectively(n=12). In addition, sample analysis was also investigated by analysis of 5-HT, MT and Trp in commercial samples obtaining an excellent quantitative and reproducible recoveries with values of 96.2 ± 1.8 %, 101.3 ± 0.2 % and 95.6 ± 1.2 % for 5-HT, MT and Trp, respectively.The current novel application reveals the analytical power of the press-transfer technology where the fast and reliable determination of MT and its precursors were performed directly on the nanoscale carbon nanotube detectors without the help of any other electrochemical transducer.