title: An amperometric detector formed of highly dispersed Ni nanoparticles embedded in a graphite-like carbon film electrode for sugar determination.
abstract: We achieved improved detection limits for sugars by developing a novel thin film containing 0.8% highly dispersed Ni nanoparticles in disordered graphite-like carbon (Ni-NDC) as a detection electrode for high-performance liquid chromatography. The Ni-NDC film was prepared in one step by a simple radio frequency (rf) sputtering method at a temperature below 200 degrees C. We characterized the film by XPS, TEM, and AFM analysis and found that the average Ni nanoparticle size was 3 nm and that the film consisted of a mixture of Ni, NiO, Ni2O3, and Ni(OH)2. We studied the electrochemical detection of sugars using the 0.8% Ni-NDC film electrode. The film electrode had excellent electrocatalytic ability and good stability compared with a Ni-bulk electrode with regard to the electrooxidation of sugars. We employed the Ni-NDC film as an HPLC detection electrode. We achieved a good separation of four sugars (glucose, fructose, sucrose, lactose) at a relatively low constant detection potential (0.40 V vs Ag/AgCl) and a linearity of over 3 orders of magnitude. We obtained improved detection limits for the investigated sugars, namely, 20, 25, 50, and 37 nM for glucose, fructose, sucrose, and lactose, respectively. This is at least 1 order of magnitude lower than the detection limits obtained with a Ni-bulk electrode with the same measurement condition. The Ni-NDC film electrode also showed good reproducibility with a relative standard deviation of 1.75% for 40 consecutive injections of glucose in a flow system.
authors.affiliation: NTT Microsystem Integration Laboratories, 3-1 Morinosato, Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
authors.forename: Tianyan
authors.initials: T
authors.lastname: You
authors.forename: Osamu
authors.initials: O
authors.lastname: Niwa
authors.forename: Zilin
authors.initials: Z
authors.lastname: Chen
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Hayashi
authors.forename: Masato
authors.initials: M
authors.lastname: Tomita
authors.forename: Shigeru
authors.initials: S
authors.lastname: Hirono
mesh_terms: D002244:Carbon / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods; D004566:Electrodes; D006108:Graphite / Q000032:analysis*; D009005:Monosaccharides / Q000032:analysis; D043942:Nanotubes / Q000032:analysis*; D009532:Nickel / Q000032:analysis*
chemical_list: D009005:Monosaccharides; D002244:Carbon; D006108:Graphite; D009532:Nickel