Anodic stripping voltammetric determination of total arsenic using a gold nanoparticle-modified boron-doped diamond electrode on a paper-based device

Abstract

A multistep paper-based analytical device (mPAD) was designed and applied to the voltammetric determination of total inorganic arsenic. The electrodeposition of gold nanoparticles on a boron-doped diamond (AuNP/BDD) electrode and the determination of total inorganic arsenic is accomplished with a single device. Total inorganic arsenic can be determined by first reducing As(V) to As(III) using thiosulfate in 1.0 mol L HCl. As(III) is then deposited on the electrode surface, and total inorganic arsenic is quantified as As(III) by square-wave anodic stripping voltammetry the potential range between -0.25 V and 0.35 V (vs. Ag/AgCl), best at around 0.05 V. Under optimal conditions, the voltammetric response for As(III) detection is linear in the range from 0.1 to 1.5 μg mL and the limit of detection (3SD/slope) is 20 ng mL. The relative standard deviation at 0.3, 0.7 and 1.0 μg mL of As(III) are 3.6, 4.3 and 3.3, respectively (10 different electrodes). The results show that the assay has high precision, a rather low working potential, and excellent sensor-to-sensor reproducibility. The method was employed to the determination of total inorganic arsenic in rice samples. Results agreed well with those obtained by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Graphical abstract A multistep paper-based analytical device (mPAD) is described that integrates a AuNP/BDD electrode preparation step and a detection step into a single device. The AuNPs are easily deposited on the BDD electrode by applying electrodeposition potential. The total inorganic arsenic concentration in rice samples was determined by using square-wave anodic stripping voltammetry.

Linker-Free Magnetite-Decorated Gold Nanoparticles (Fe3O4-Au): Synthesis, Characterization, and Application for Electrochemical Detection of Arsenic (III)

“…Electrodes of various nano-materials/particles, such as carbon nanotubes, metal oxides, noble metals (Au, Ag and Pt), and graphene, have been used for As(III) determination [ 15 , 16 , 17 , 18 ]. Previous reports demonstrated that AuNPs-modified electrodes could enhance the anodic current response toward As(III) more effectively than other materials relying on chemical reduction by electrogenerated H 2 [ 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. However, these methods need strong acidic conditions to guarantee enough electrogenerated H 2 availability for electrochemical reduction of As(III) to As(0) during the electrochemical reduction/deposition step.…”

A review on advances in methods for modification of paper supports for use in point-of-care testing

“…A wax-based technology was applied to modify hydrophobic patterns and hydrophobic barriers on paper using a wax printer [27] and a pen-writing approach [28]. Different nanomaterials, such as quantum dots (QDs) [29][30][31][32][33], gold nanoparticles (AuNPs) [24,[34][35][36][37][38][39][40][41][42][43][44][45][46], AuNFs MBA @Ag [47] Cu-Pd/rGO nanoparticles [48], upconverting fluorescent nanocrystals [49], metal-organic framework [50], fluorescent nanoparticles [51], gold nanocage [52], gold nanorods [53], multi-walled carbon nanotubes and graphene oxide [54] and polymer nanoparticles [55], have also been used as reading signal in paper-based POCT devices. The functional papers prepared by these advanced modification approaches significantly extend the application potential of paper as the substrate of POCT devices.…”

A Review of Microfluidic Detection Strategies for Heavy Metals in Water

“…This issue could be mitigated by introducing filtration systems in microfluidic detection devices [46]. Numerous strategies for solving interference problems have been developed; Zhang et al used solid phase absorption to overcome interference [105], Chowdury et al adjusted pH to prevent iron interference on arsenic determination [79]; Punjunum et al used ferricyanide for copper interference elimination [164]. In general, however, more extensive research is needed to assess the capability of microfluidic detection systems to produce reliable and reproducible measurements in a wide range of complex environmental water matrices.…”

“…The LOD was found to be 20 μg L −1 , and the linear range was between from 0.1-1.5 mg L −1 . Although copper was found to interfere with the detection of arsenic, ferricyanide was used to complex copper and overcome the interference [164].…”