Batch-Injection Amperometric Determination of Pyrogallol in Biodiesel Using a Multi-Walled Carbon Nanotube Modified Electrode

Abstract

This work demonstrates the application of batch-injection analysis (BIA) with amperometric detection on a multi-walled carbon nanotube (MWCNT) modified electrode for the sensitive determination of the antioxidant pyrogallol in biodiesel. Samples were diluted in electrolyte (0.1 mol L-1 HClO 4) before injection using an electronic micropipette on the BIA cell. The size effect of MWCNTs on electrochemical oxidation of pyrogallol was investigated and 3.5-fold increase in the amperometric sensitivity using the modified electrode with MWCNTs of shorter dimensions was obtained. This result was in agreement with cyclic voltammetry and electrochemical impedance spectroscopy measurements. After optimization of BIA parameters for the amperometric detection on the MWCNT-modified electrode, the proposed method presented a linear range from 0.3 to 1000 µmol L-1 , detection limit of 0.013 µmol L-1 , precision of 3%, and sample throughput of 240 h-1. Spiked biodiesel samples were analyzed and recovery values between 95-99% were obtained.

A low-cost carbon-based electrochemical platform for determining 2,3-dihydroxyphenol: applications in natural water and biodiesel samples

“…The calculated LOD was 0.03 μmol L −1 , obtained from equation 3 × SD b / b , where SD b is the standard deviation of the blank and b is the slope of the analytical curve. The LOD and the linear range were compared to other methods for determining DHP (Table 4 1,2,11–13,16,20,38–45 ).…”

“…Several materials have been reported as modiers in these electrodes such as polymers, carbon-based materials, organic and inorganic compounds, and hybrids. [14][15][16][17][18][19][20][21][22] Some electrodes such as carbon paste electrodes (CPE) can be easily modied. CPE are electrodes made from a mixture of a carbon-based material (usually graphite powder) with a binder and have the advantages of being easily prepared, low cost, high stability and low background current.…”

“…A disadvantage of CNT is the high manufacturing cost. [14][15][16][22][23][24] In this context, the purpose of this work was to study the voltammetric behavior of DHP on carbon paste electrodes in order to evaluate the better carbon material (platform) for simple and low-cost electrochemical determining DHP in natural water and biodiesel samples.…”

Batch injection analysis in tandem with electrochemical detection: the recent trends and an overview of the latest applications (2015–2020)

“…BIA has been applied for determination of organic molecules in other miscellaneous samples, such as jet fuel, seized sample, and biodiesel [ 97 , 100 , 101 , 104 – 106 ]. In addition, it was also undertaken to monitor electrochemical properties of model organic substances on unmodified or modified electrode surfaces [ 98 , 99 , 102 , 103 ].…”

Lucigenin-pyrogallol chemiluminescence for the multiple detection of pyrogallol, cobalt ion, and tyrosinase

“…In addition, PG structural group is found in several important natural molecules such as gallic acid (GA) and tannic acid (TA). Different analytical techniques were reported for detection of PG such as spectrophotometry [ 14 – 16 ], chromatographic techniques [ 17 – 20 ], and electrochemical methods [ 21 – 24 ]. However, most of these methods especially chromatographic techniques involve tedious sample preparation and complicated analytical procedures that are time-consuming and use toxic organic solvents.…”