Detection of Phosphate in Human Blood Based on a Catalytic Hydrogen Wave at a Molybdenum Phosphide Modified Electrode

Abstract

Detection of inorganic phosphate is very important in environmental and health care applications. In this work, we found that phenomenon similar to “catalytic hydrogen wave” occurred on a molybdenum phosphide (MoP) modified electrode in the presence of phosphate, that is, a new wave of catalytic hydrogen evolution appeared before the normal hydrogen evolution reaction. The catalytic hydrogen wave arose from a structure similar to phosphomolybdic acid (noted as MoPO), which was formed by the interaction between phosphate and molybdenum oxides on the surface of the MoP modified electrode, resulting in the altered surface structure and adjusted interface catalytic activity. A novel phosphate electrochemical sensor was constructed based on this phenomenon with a linear range from 0.10 to 20.0 mmol·L–1, an actually determined minimum concentration of 0.030 mmol·L–1, and recoveries of 94%–107%, and this sensor was successfully applied to the detection of phosphate in human blood. Furthermore, this work proposes a new sensing method based on catalytic hydrogen waves on the modified electrodes.

Multi-Oxyanion Detection by an Organic Field-Effect Transistor with Pattern Recognition Techniques and Its Application to Quantitative Phosphate Sensing in Human Blood Serum

“…The obtained nonlinear titration curve implied that the OFET successfully captured Pi on the Cu II -dpa complex-based SAM, and the estimated limit of detection by the 3σ method showed 2.8 μM. The calculated detection limit was lower than a previously reported Faraday current based electrochemical sensor . Because of such low LoD, the OFET-based sensor would potentially predict some symptoms such as hypophos­phatemia (i.e., the low concentration of phosphate in blood) .…”

“…The calculated detection limit was lower than a previously reported Faraday current based electrochemical sensor. 86 Because of such low LoD, the OFET-based sensor would potentially predict some symptoms such as hypophosphatemia (i.e., the low concentration of phosphate in blood). 8 Certainly, a peak assigned as P 2p (∼132.6 eV) 87 in the XPS measurement supported the coordination of Pi on the extended-gate electrode (Figure 3b, inset).…”

Gold-dispersed hierarchical flower-like copper oxide microelectrodes for the sensitive detection of glucose and lactic acid in human serum and urine

“…[20][21][22][23][24] Generally, conventional working substrates including glassy carbon (GC), polycrystalline gold (Au) and platinum (Pt) disk electrodes are used as sensing electrodes in the design of new analytical methods. [25][26][27][28][29] Owing to the undesirable chemical or electrochemical pre-treatment each time, bulk dimension and laborious process, a new design of miniaturized sensing platform is required. [30][31][32][33][34] Compared to the macroelectrode or conventional electrodes, microelectrode-based signal transducers exhibit rapid response/recovery time, small measured currents with a low ohmic drop (IR), and improved mass transfer rate, and therefore, they are used in the design of high-performance electrochemical sensor systems.…”

Direct Electrochemical Sensing of Phosphate in Aqueous Solutions Based on Phase Transition of Calcium Phosphate

“…21 A molybdenum phosphide-modified electrode was recently used to detect phosphate in human blood based on catalytic hydrogen evolution. 22 Most of these existing strategies are based on electrochemical peaks in negative potential ranges, which would be inevitably influenced by dissolved oxygen during the electrochemical sensing process. Calcium phosphates (CaPs) are the main inorganic constituents of bone and teeth 23 and are considered as one of the most important biomaterials and used for bone regeneration, 24 tooth enamel repair, 25 drug delivery 26 and antibacterial application.…”

“…In this respect, cobalt-based electrodes were designed to monitor phosphate; however, constant oxygen feeding operations were required, which complicated the detection procedures. − Combined with the flow injection analysis, an activated nickel platform was proposed to monitor phosphate in the biological system . A molybdenum phosphide-modified electrode was recently used to detect phosphate in human blood based on catalytic hydrogen evolution . Most of these existing strategies are based on electrochemical peaks in negative potential ranges, which would be inevitably influenced by dissolved oxygen during the electrochemical sensing process.…”