Portable electrochemical analytical devices such as cholesterol sensors are widely used for disease diagnosis. However, these tools are bulky and require bioreceptors for the specific detection of cholesterol. Herein, a novel 3D electrochemical paper-based analytical device (3D-ePAD) combined with a near-field communication (NFC) potentiostat was developed and applied to the nonenzymatic detection of cholesterol.
View Article and Find Full Text PDFA portable device offering effortlessness, mobility, and affordability for real-time and on-site monitoring of heavy metals is currently in great demand to maintain environmental sustainability. Herein, a platform utilizing a biopolymeric gel-based electrolyte for the on-field simultaneous determination of Cd(II) and Pb(II) is described. Pectin, a natural polymer, was exploited as a chemical delivery medium on account of its biodegradability, environmental friendliness, and rapid dissolving characteristics.
View Article and Find Full Text PDFAn automated microfluidic electrochemical platform was developed for the rapid in-field analysis of arsenic speciation. Herein, we integrated an electrochemical sensing and microfluidic channel for the simultaneous determination of As(III) and total inorganic As (total iAs) within a single device. The platform was fabricated by assembling a gold nanoparticle-modified screen-printed graphene electrode (AuNP/SPGE) on a hydrophilic polyethylene terephthalate (PET) sheet that was specially designed to enclose a microfluidic channel with dual flow channels for separate determination of the two species.
View Article and Find Full Text PDFThe electrochemical determination of five heavy metals is demonstrated using a wireless and card-sized potentiostat coupled with a smartphone through near-field communication (NFC) technology. A smartphone application was customized to command the NFC potentiostat, collect real-time signals, process the data, and ultimately display the quantities of the selected elements. The screen-printed graphene electrode (SPGE) was simply fabricated and modified using different nanomaterials for each heavy metal.
View Article and Find Full Text PDFA microcapillary grooved paper-based analytical device capable of dual-mode sensing (colorimetric and electrochemical detection) was demonstrated for analysis of viscous samples (e.g., human saliva).
View Article and Find Full Text PDFIn this work an electrochemical immunosensor for the toxic microalgae Alexandrium minutum (A. minutum AL9T) detection is described. A glassy carbon electrode (GCE) was modified by depositing gold nanoparticles followed by L-cysteine for obtaining a self-assembled monolayer.
View Article and Find Full Text PDFA disposable gas-sensing paper-based device (gPAD) was fabricated in origami design which integrates the gas adsorbent and the electrochemical detection zone in a single device. The gPAD for the determination of NOx gas uses a screen-printed graphene electrode modified with copper nanoparticles (CuNP/SPGE) to achieve high sensitivity and selectivity. The gPAD detects both, NO and NO (as NOx) with same current responses.
View Article and Find Full Text PDFA 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.
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