title: Electrochemical detection of p-ethylguaiacol, a fungi infected fruit volatile using metal oxide nanoparticles.
abstract: Nanoparticles of TiO(2) or SnO(2) on screen-printed carbon (SP) electrodes have been developed for evaluating their potential application in the electrochemical sensing of volatiles in fruits and plants. These metal oxide nanoparticle-modified electrodes possess high sensitivity and low detection limit for the detection of p-ethylguaiacol, a fingerprint compound present in the volatile signature of fruits and plants infected with a pathogenic fungus Phytophthora cactorum. The electroanalytical data obtained using cyclic voltammetry and differential pulse voltammetry showed that both SnO(2) and TiO(2) exhibited high sensitivity (174-188 μA cm(-2) mM(-1)) and low detection limits (35-62 nM) for p-ethylguaiacol detection. The amperometric detection was highly repeatable with RSD values ranging from 2.48 to 4.85%. The interference studies show that other common plant volatiles do not interfere in the amperometric detection signal of p-ethylguaiacol. The results demonstrate that metal oxides are a reasonable alternative to expensive electrode materials such as gold or platinum for amperometric sensor applications.
authors.affiliation: Nano Electrochemistry Laboratory, College of Engineering, University of Georgia, Athens, GA 30602, USA. rama@uga.edu.
authors.forename: Yi
authors.initials: Y
authors.lastname: Fang
authors.forename: Yogeswaran
authors.initials: Y
authors.lastname: Umasankar
authors.forename: Ramaraja P
authors.initials: RP
authors.lastname: Ramasamy
mesh_terms: D055664:Electrochemical Techniques / Q000295:instrumentation*; D004566:Electrodes; D005638:Fruit / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D006139:Guaiacol / Q000031:analogs & derivatives* / Q000032:analysis; D054884:Host-Pathogen Interactions; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D010838:Phytophthora / Q000502:physiology; D010944:Plants / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D017971:Tin Compounds / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D017971:Tin Compounds; C009495:titanium dioxide; D006139:Guaiacol; C084991:4-ethylguaiacol; D014025:Titanium; C045358:stannic oxide