Fast and Sensitive Detection of Pb2+ in Foods Using Disposable Screen-Printed Electrode Modified by Reduced Graphene Oxide

Abstract

In this study, reduced graphene oxide (rGO) was electrochemically deposited on the surface of screen-printed carbon electrodes (SPCE) to prepare a disposable sensor for fast detection of Pb2+ in foods. The SEM images showed that the rGO was homogeneously deposited onto the electrode surface with a wrinkled nanostructure, which provided 2D bridges for electron transport and a larger active area for Pb2+ adsorption. Results showed that rGO modification enhanced the activity of the electrode surface, and significantly improved the electrochemical properties of SPCE. The rGO modified SPCE (rGO-SPCE) was applied to detect Pb2+ in standard aqueous solution, showing a sharp stripping peak and a relatively constant peak potential in square wave anodic stripping voltammetry (SWASV). The linear range for Pb2+ detection was 5∼200 ppb (R2 = 0.9923) with a low detection limit of 1 ppb (S/N = 3). The interference of Cd2+ and Cu2+ at low concentrations was effectively avoided. Finally, the rGO-SPCE was used for determination of lead in real tap water, juice, preserved eggs and tea samples. Compared with results from graphite furnace atomic absorption spectroscopy (GFAAS), the results based on rGO-SPCE were both accurate and reliable, suggesting that the disposable sensor has great potential in application for fast, sensitive and low-cost detection of Pb2+ in foods.

A Screen Printed Phenanthroline-Based Flexible Electrochemical Sensor for Selective Detection of Toxic Heavy Metal Ions

“…5. The reduction potential of −0.6 eV, obtained for Pb 2+ with the printed sensor, is comparable to reported literature values [43]. These results indicated that the sensor only provided a response when brought in contact with Pb 2+ , however, no response was detected when the sensor was brought in contact with Hg 2+ ions.…”

p53‐competent cells and p53‐deficient cells display different susceptibility to oxygen functionalized graphene cytotoxicity and genotoxicity

“…Graphene possesses unique optical, electrical, and thermal conductivity properties, as well as ultra‐thinness, and flexibility that makes graphene and its derivatives attractive for use in numerous areas of industry and biomedicine. Proposed uses for graphene‐based materials include molecular biosensors (Jian et al, ; Yan et al, ), bacterial detectors and antimicrobial surface treatments (Hu et al, ; Mannoor et al, ), filters for water purification (Subramani & Jacangelo ; Surwade et al, ), modifying gas barriers and adhesives for use in food packaging (Hu et al, ; Xiang et al, ), and wound dressing materials that promote accelerated healing (Fan et al, ; Lu et al, ). Also, graphene derivatives are potentially useful as components of medical implants (Lahiri et al, ; Aryaei et al, ), drug delivery platforms (Ma et al, ; Saeed et al, ), photothermal therapies (Qin et al, ; Nedosekin et al, ), and as scaffolding for tissue regeneration/engineering (Mahmood et al, ; Elkhenany et al, ).…”

Single Frequency Impedance Analysis on Reduced Graphene Oxide Screen-Printed Electrode for Biomolecular Detection

“…1). The cathodic current peak at −1.4 V is due to the irreversible electrochemical reduction of several oxygen-containing functional groups on the surface of GO [31]. A decrease in the reduction peak with increasing CV scans to almost a disappearing state confirms a near completion of the reduction of GO to rGO, as evident in Fig.…”