Development of a Novel, Low-Cost, Disposable Wooden Pencil Graphite Electrode for Use in the Determination of Antioxidants and Other Biological Compounds.
The development of portable sensors that can be used outside the lab is an active area of research in the electroanalytical field. A major focus of such research is the development of low-cost electrodes for use in these sensors. Current electrodes, such as glassy-carbon electrodes (GCEs), are costly and require time-consuming preparation. Alternatives have been proposed, including mechanical pencil-lead electrodes (MPEs). However, MPEs themselves possess numerous drawbacks, particularly structural fragility. In this paper, we present a novel pencil-graphite electrode (PGE) fabricated from a regular HB#2 pencil. This PGE is a simple, disposable, extremely low-cost alternative to GCEs ($0.30 per PGE, vs. $190 + per GCE), and possesses the structural stability that MPEs lack. PGEs were characterized by square-wave voltammetry of ferricyanide, gallic acid, uric acid, dopamine, and several foodstuffs. In all cases, PGEs demonstrated sensitivities comparable or superior to those of the GCE and MPE (LOD = 5.62 × 10(-4) M PGE, 4.80 × 10(-4) M GCE, 2.93 × 10(-4) M MPE). Signal areas and peak heights were typically four to ten times larger for the PGE relative to the GCE.
Department of Science, Augustana Campus, University of Alberta, 4901-46th Ave, Camrose, AB T4V 2R3, Canada. jkariuki@ualberta.ca.
James
J
Kariuki
Department of Science, Augustana Campus, University of Alberta, 4901-46th Ave, Camrose, AB T4V 2R3, Canada. eervin@ualberta.ca.
Emily
E
Ervin
Department of Science, Augustana Campus, University of Alberta, 4901-46th Ave, Camrose, AB T4V 2R3, Canada. caolafso@ualberta.ca.
Carly
C
Olafson
D000975:Antioxidants / Q000032:analysis*; D002244:Carbon / Q000737:chemistry; D003365:Costs and Cost Analysis; D055664:Electrochemical Techniques / Q000191:economics* / Q000379:methods*; D004566:Electrodes / Q000191:economics; D005292:Ferricyanides / Q000032:analysis; D005638:Fruit / Q000737:chemistry; D005707:Gallic Acid / Q000032:analysis; D005898:Glass / Q000737:chemistry; D006108:Graphite / Q000737:chemistry* / Q000191:economics*; D007854:Lead / Q000737:chemistry; D012015:Reference Standards; D015203:Reproducibility of Results; D014675:Vegetables / Q000737:chemistry; D014934:Wood / Q000737:chemistry*
D000975:Antioxidants; D005292:Ferricyanides; C007931:hexacyanoferrate III; D007854:Lead; D005707:Gallic Acid; D002244:Carbon; D006108:Graphite
antioxidant; biosensor; glassy carbon electrode; pencil graphite electrode; square-wave voltammetry