Stripping voltammetric detection of copper ions using carbon paste electrode modified with aza-crown ether capped gold nanoparticles and reduced graphene oxide

In this work, a novel electrochemical sensor was presented for Tanshinone IIA determination. The as-prepared electrode was prepared by electrodepositing a reduced graphene oxide film onto a carbon paste electrode modified with gold nanoparticles, which combined the advantages of both gold nanoparticles and electrochemically reduced graphene oxide. It was characterized with scanning electron microscopy and cyclic voltammetry. The electrochemical behavior of Tanshinone IIA at the modified electrode was investigated for the first time. Results revealed that the modified electrode can effectively increase response toward Tanshinone IIA by significantly enhancing the redox peak currents and decreasing the peak-to-peak separation. Under the optimized conditions, the modified electrode showed a linear voltammetric response to Tanshinone IIA at concentrations ranging from [Formula: see text][Formula: see text]mol L[Formula: see text] to [Formula: see text][Formula: see text]mol L[Formula: see text], with a detection limit of [Formula: see text][Formula: see text]mol L[Formula: see text] ([Formula: see text]). The proposed method was successfully applied in determination of Tanshinone IIA in pharmaceutical samples with satisfactory results.

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A Novel Reduced Graphene Oxide Modified Carbon Paste Electrode for Potentiometric Determination of Trihexyphenidyl Hydrochloride in Pharmaceutical and Biological Matrices

Sensors ◽

10.3390/s21092955 ◽

2021 ◽

Vol 21 (9) ◽

pp. 2955

Author(s):

Josip Radić ◽

Maša Buljac ◽

Boštjan Genorio ◽

Ema Gričar ◽

Mitja Kolar

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Carbon Paste Electrode ◽

Anticholinergic Drug ◽

Modified Carbon Paste Electrode ◽

Carbon Paste ◽

Experimental Conditions ◽

Electroactive Material ◽

Reduced Graphene ◽

Paste Electrode

A novel promising carbon paste electrode with excellent potentiometric properties was prepared for the analysis of trihexyphenidyl hydrochloride (THP), the acetylcholine receptor and an anticholinergic drug in real samples. It contains 10.2% trihexyphenidy-tetraphenylborate ionic pair as the electroactive material, with the addition of 3.9% reduced graphene oxide and 0.3% of anionic additive into the paste, which consists of 45.0% dibutylphthalate as the solvent mediator and 40.6% graphite. Under the optimized experimental conditions, the electrode showed a Nernstian slope of 58.9 ± 0.2 mV/decade with a regression coefficient of 0.9992. It exhibited high selectivity and reproducibility as well as a fast and linear dynamic response range from 4.0 × 10−7 to 1.0 × 10−2 M. The electrode remained usable for up to 19 days. Analytical applications showed excellent recoveries ranging from 96.8 to 101.7%, LOD was 2.5 × 10−7 M. The electrode was successfully used for THP analysis of pharmaceutical and biological samples.

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