Determination of heavy metals in root crops using bismuth nanoparticles modified graphene paste electrode
Vaata/ Ava
Aasta
2019Autor
Palisoc, S.
Malabuyo, Y.A.
Pereja, R.C.
Natividad, M.
Metadata
Näita täielikku nimetuse kirjetKokkuvõte
Electrochemical detection of lead (Pb2+) and cadmium (Cd2+) was accomplished via
anodic stripping voltammetry (ASV) using bismuth nanoparticle (BiNP) modified graphene paste
electrode (GPE). The electrode was fabricated by mixing bismuth nanoparticles, graphene, and
mineral oil and the mixture was packed in a Teflon syringe. The best electrode was determined
by varying the amount of BiNP while the amount of graphene and mineral oil were kept constant
at 0.21 g and 0.80 μL, respectively. The highest peak currents were obtained using 1.5 mg BiNP
modified GPE. The ASV parameters, namely accumulation time, deposition time, and
accumulation potential, were optimized. The calibration curve, analytical sensitivity, limit of
detection (LOD), and limit of quantitation (LOQ) of the optimized electrode were determined.
The correlation values for Pb2+ (R2 = 0.9409) and Cd2+ (R2 = 0.9086) in the calibration curves
showed a positive linear relationship between the anodic peak current and heavy metal
concentration. The LOD for both Pb2+ and Cd2+ is found to be 100 ppb. The application of the
modified electrode on real sample analysis was performed using root crops purchased from local
supermarkets. According to ASV and AAS analyses, most of the samples contained Cd2+ while
only a few contained Pb2+. Other metals, such as Fe2+ and Cu2+, were also detected via ASV.