Platinum Nanoparticles Decorated Multiwalled Carbon Nanotubes – Ionic Liquid Composite Film Coated Glassy Carbon Electrodes for Sensitive Determination of Theophylline

Abstract

[PF 6 ], more Pt nano could deposit on MWCNTs. The average diameter of the deposited Pt nano was about 5 nm. The composite material film coated glassy carbon electrode (GCE) exhibited sensitive voltammetric response to theophylline (TP). Under the optimized conditions (i.e., preconcentration for 2 minutes on open circuit in 0.10 M pH 3.0 phosphate buffer), the anodic peak current of TP at about 1.1 V (vs. SCE) was linear to TP concentration over the range of 1.0 Â 10 À8 -1.0 Â 10 À5 M. The detection limit was estimated to be 8.0 Â 10 À9 M. The modified electrode was successfully applied to the determination of TP in medicine tablet and green tea. In addition, the voltammetric responses of hypoxanthine (HX), xanthine (Xan) and uric acid (UA) on the MWCNTs-Pt nano -[omim] [PF 6 ]/GCE were also discussed.

Determination of Theophylline at a Cysteic Acid Modified Glassy Carbon Electrode

“…Several solutions were proposed, including the use of electrodes with a wider positive potential range [17], modified electrodes [19 -21] or unusual combination of solvent/supporting electrolyte [22]. In recent times, carbon nanotubes modified [23,24] and molecular imprinted [25] electrodes were also proposed for the determination of theophylline.…”

Prepeak of trolox caused by theophylline and its application to the determination of theophylline in rat plasma

“…The oxidation potentials of theophylline at a glassy carbon electrode (GCE) and a boron-doped diamond electrode (BDDE) in Britton-Robinson buffer (pH 1.8) were +1.25 V and +1.3 V vs. SCE, respectively [9]. Several modified electrodes were also developed to detect theophylline with high sensitivity [10][11][12][13]. Furthermore, sensing it without its direct oxidation at an electrode was examined using the enzyme electrodes [14][15][16][17] or an electrochemical RNA aptamer [18][19][20][21].…”

Voltammetric determination of theophylline at a Nafion/multi-wall carbon nanotubes composite film-modified glassy carbon electrode

“…13 Thus, they are exploited for the determination of theophylline. In order to enhance the sensitivity and stability of the measurements, the electrodes modified with designable molecules have been used in electrochemical determination of theophylline, but electroanalysis of theophylline were seldom reported [14][15][16][17][18][19] because of the oxidation of theophylline occurring at a very high positive potential and apt congregating on electrode surface. For instance, Zen et al employed a Nafion/leadruthenium oxide pyrochlore chemically modified electrode for the voltammetric determination of TP in tea and drug formulation with a detection limit of 1⋅0 × 10 -7 mol/L.…”