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A method employing high-performance liquid chromatography with electrochemical detection (LC-ED) has been successfully developed for the determination of uric acid in human salvia. The optimal chromatographic conditions were found to comprise a mobile phase containing 5 % methanol, 95 % 50 mM trichloroacetic acid, adjusted to pH 2.7, in conjunction with a Hypersil C18 250 mm x 4.6 mm column at ...

A simple, selective and sensitive electrochemical method is described for the determination of different aldehydes at glassy carbon electrode using electrochemical impedance spectroscopy (EIS). The measurements were performed after their derivatization with 2,4-dinitrophenylhydrazine (DNPH) in acidic medium. The impedance measurements were investigated in the frequency range from 100 mHz to 100...

A simple and sensitive electrochemical sensor fabricated with graphene nanosheets (GNs) and a hydroxyapatite (HA) nanocomposite-modified glassy carbon electrode (GCE) was developed for the determination of matrine (MT). The as-prepared electrode (GNs/HA/GCE) was verified to outperform bare a GCE and GNs-modified electrode with increased oxidation peak currents and the decreased over-potential i...

A rapid multiresidue method has been developed for the analysis of seven phenylurea herbicides in the presence of two s-triazines in environmental waters. A simple end-column electrochemical detector was used in combination with a commercially-available capillary electrophoresis instrument with UV detection. The determination of phenylurea pesticides using micellar electrokinetic capillary chro...

fabrication and electrochemical characterization of a sensor for the determination of epinephrine (ep), uric acid (ua) and folic acid (fa) is described. the sensor  was prepared using carbon paste electrode (cpe) modified with 3,4-dihydroxybenzaldehyde-2,4-dinitrophenylhydrazone (ddp) and carbon nanotubes (cnts), which makes the modified electrode highly sensitive for the electrochemical detect...

investigation of the redox properties of drugs and their determination are performed by electrochemical techniques. data obtained from electrochemical techniques are often correlated with molecular structure and pharmacological activity of drugs. in this regard, different modified electrodes were applied as sensors for quantification of different drugs.a nanocomposite of reduced graphene oxide-...

A poly(methylene blue)-modified glassy carbon electrode (PMB/GCE) was fabricated by electropolymerisation of methylene blue on a GCE and further utilized to investigate the electrochemical determination of 4-nitrophenol (4-NP) by cyclic voltammetry (CV), differential pulse voltammetry and chronocoulometry. The morphology of the PMB on GCE was examined using a scanning electron microscope (SEM)....

A simple and high sensitive electrochemical method was developed for determination of phenylephrine (PHE) in the presence of acetaminophen (AC) at the carbon-ceramic electrode modified by multi-walled carbon nanotubes/ionic liquid nanocomposite (MWCNTs/IL/CCE). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) and chronoamperometry methods were used for electrochemical studie...