A sulfite sensor based on electrocatalytic oxidation at a phenothiazine drop-coated screen-printed carbon electrode

https://doi.org/10.1016/j.jelechem.2012.04.016Get rights and content

Abstract

This paper describes an easy-to-prepare and disposable sulfite sensor using a phenothiazine drop-coated screen printed carbon electrode (PhSPCE) in couple with flow injection analysis. It was found that the PhSPCE possesses electrocatalytic activity toward the oxidation of sulfite with relatively high sensitivity, selectivity, good stability and reproducibility. The linear working range for the determination of sulfite was 0.6 ppm to 200 ppm with a detection limit of 0.28 ppm. The proposed method was successfully applied to the determination of sulfite in real samples.

Highlights

Phenothiazine was drop-coated on screen printed carbon electrode. ► Combined advantages of rapid, easy-to-prepare and disposable. ► High electrocatalytic activity towards sulfite. ► The developed method can determine sulfite in real samples with satisfactory results.

Introduction

Researches have been focused on the detection of sulfite due to its potential toxicity but widely used as a preservative in the food and beverage industries. The US Food and Drug Administration regulations have indicated that the sulfite ions contained in food and beverage should not exceed 10 ppm [1]. Besides, sulfite is also used in boilers and boiler-feed waters for dissolved oxygen control. Therefore a simple and effective method for the analysis of sulfite in these products is required. Many analytical methods for the sulfite assay have been reported, such as high performance liquid chromatography [2], [3], capillary electrophoresis [4], chemiluminescence [5], and spectrophotometry [6]. Compared to electrochemical detections, these techniques are not convenient. Therefore, there is still an increasing demand in electrochemical detections, as these generally have the advantages of simplicity, short analysis time, low cost, high reproducibility, and sensitivity.

To achieve sensitivity and selectivity, most of the electrochemical techniques utilize a tailor made chemically modified electrode [7], [8], [9], [10], [11], [12], [13], [14], [15], [16]. Kalimuthu et al. used a combination of Starkeya novella sulfite dehydrogenase, horse heart cytochrome c, and a self-assembled monolayer of 11-mercaptoundecanol cast on a gold electrode for the determination of sulfite [9]. Spricigo et al. developed an electrocatalytic biosensor for sulfite detection by co-immobilizing sulfite oxidase and cytochrome c with polyaniline sulfonic acid in a layer-by-layer assembly [13]. Siroueinejad et al. reported the electrocatalytic oxidation of sulfite at a stable electroactive thin film of copper–cobalt hexacyanoferrate hybrid electrodeposited on a carbon paste electrode [12]. However, the complicating electrode preparation steps, high cost of enzyme and the decrease of enzyme activity by immobilization limit the practical application of these electrodes.

Phenothiazine (Ph) and its derivatives represent one of the most interesting groups of monomers used to obtain electropolymerized films with high electrocatalytic activity for NADH oxidation [17], [18]. In addition to be electropolymerized on electrodes, these compounds can also be physisorbed on electrodes by a simple drop-coating procedure but still keep high electrocatalytic efficiency for NADH oxidation [19]. In this study, we report a simple electrochemical approach using a phenothiazine drop-coated disposable screen printed carbon electrode (PhSPCE) for flow injection analysis (FIA) of sulfite. Since the proposed system had the combined advantages of low cost, versatility, and miniaturization (from screen-printing technique), ease of electrode modification (from drop-coating procedure), as well as being rapid, reproducible, and simple (from FIA technique), it represented a useful platform for the routine determination of sulfite.

Section snippets

Materials and instruments

All chemicals used are of ACS-certified reagent grade. Aqueous solutions were prepared with double distilled deionized water. Electroanalytical measurements were carried out using a CHI824b electrochemical workstation (CH Instruments, Austin, TX) with conventional 10 mL working cell. The SPCE (SE100-HD) was obtained from Zensor (Taichung, Taiwan). The diameter of the working area was 0.196 cm2. The three electrode system consisted of the PhSPCE working electrode, an Ag/AgCl reference electrode

Characterization of the modified electrode

The ATR FT-IR spectrum, as shown in Fig. 1, verifies that the modified electrode surface is covered densely with Ph. The obtained data are in very good agreement to the literature [20]. A band at 657 cm−1 is attributed to a complex vibration with δ(CCC), γ(NH), and δ(CNC) and 684 cm−1 is assigned as a complex vibration with δ(CCC), ν(CSC), and δ(CN). In the mid-IR region, 860 and 880 cm−1 corresponds to δ(CN), δ(CCC) and δ(NH), 1030 cm−1 belongs to δ(CCC) and ν(CSC), 1304 cm−1 is assigned to ν(Cdouble bondC)

Conclusions

In conclusion, Ph modified electrode has been successfully fabricated by a simple drop-coating procedure on a disposable SPCE. FIA coupled with PhSPCE is a new, simple, and effective method for sulfite determination with good analytical properties such as rapid, stable, reproducible, selective and sensitive. Furthermore, without the use of expensive metals or enzymes, a good catalytic response of the sensors is obtained in this method. Extended practical assay for the real samples gave

Acknowledgments

The authors would like to thank the National Science Council of Republic of China (Taiwan) for financial support under Contract No. NSC 98-2113-M-126-005-MY3.

References (21)

  • M. Iammarino et al.

    Anal. Chim. Acta

    (2010)
  • M. Masár et al.

    J. Chromatogr. A

    (2005)
  • S.S.M. Hassan et al.

    Anal. Chim. Acta

    (2006)
  • A.A. Ensafi et al.

    Int. J. Electrochem. Sci

    (2010)
  • J.B. Raoof et al.

    Int. J. Electrochem. Sci

    (2007)
  • L.S.T. Alamo et al.

    Talanta

    (2010)
  • D. Gligor et al.

    Electrochim. Acta

    (2009)
  • D. Dicu et al.

    Electrochim. Acta

    (2000)
  • F. Register

    Food Label: Declarat. Sulf. Agents

    (1986)
  • M. Koch et al.

    J. Agric. Food Chem.

    (2010)
There are more references available in the full text version of this article.

Cited by (16)

  • Phenothiazine-coumarin-pyridine hybrid as an efficient fluorescent probe for ratiometric sensing hypochlorous acid

    2021, Microchemical Journal
    Citation Excerpt :

    It is noticeable that phenothiazine is an important molecular structural unit, which can endow the compounds with special properties, such as biological activity [47], photoelectric characteristics [48], electrical conductivity [49,50], etc. Phenothiazine derivatives have been widely used in many fields, including medicinal chemistry [51], electroluminescence [52,53], photovoltaics [54,55], batteries [56,57], supercapacitors [58,59], electrochemical detection [60,61], fluorescence sensing [62,63], and so on. Recent reports also show that phenothiazine-infused coumarin derivatives can function as efficacious probes for the ratiometric sensing of HOCl [64–66].

  • A highly sensitive determination of sulfite using a glassy carbon electrode modified with gold nanoparticles-reduced graphene oxide nano-composites

    2017, Journal of Electroanalytical Chemistry
    Citation Excerpt :

    Therefore, non-enzymatic sulfite electrochemical sensors have been received keen interests and developed rapidly due to the advantages of the thermal and chemical stability, as well as high sensitivity. For example, electrodes modified with phenothiazine [8], copper-salen [9], Ru-complex [10], metal hexacyanoferrates (MHCF), including PB [11], CoHCF [12,13], PrHCF [14], CuHCF [15] and nickel pentacyanonitrosylferrate [16], ferrocene [17], graphene and its composite [18,19], ionic liquid [20] have been used for the determination of sulfite in various food samples. On the other hand, gold nanoparticles (AuNPs) have outstanding electronic conductivity, high surface area and electrochemical activity that make them promising materials in the fields of electrochemical sensing [21].

  • An electrochemical approach: Switching Structures of rare earth metal Praseodymium hexacyanoferrate and its application to sulfite sensor in Red Wine

    2015, Electrochimica Acta
    Citation Excerpt :

    On the other hand, sulfite is a food preservative agent that has been widely used in wines, dried fruits, and boilers industries to assist the anti-oxidation and microbial spoilage [18–20]. Nonetheless, excess sulfite ions in food and other drinks leads to toxicity and they are proven detrimental to the health of human beings [21–24]. Besides, the excess levels of sulfite in natural aquatic system reduced the dissolved oxygen in water, causing drastic effects to aquatic organism [25].

  • Simple flow injection for determination of sulfite by amperometric detection using glassy carbon electrode modified with carbon nanotubes-PDDA-gold nanoparticles

    2015, Talanta
    Citation Excerpt :

    The method required an acid distillation to extract the sulfur dioxide gas from sample matrices prior to analysis and the conventional titrimetric method suffers from poor precision and long analysis time. Many analytical methods for the sulfite assays such as spectrophotometry [9,10], chemiluminescence [4,11], capillary electrophoresis [12] and electrochemical detections [13–18] have been reported. Among these methods, electrochemical detection is most attractive because of its high sensitivity, simplicity, rapid response and inexpensive equipment.

View all citing articles on Scopus
View full text