Boron-Doped Graphene Quantum Dots Anchored to Carbon Nanotubes as Noble Metal-Free Electrocatalysts of Uric Acid for a Wearable Sweat Sensor

Abstract

Emerging wearable devices with noninvasive biosensing technologies have sparked substantial interest for constant monitoring of substances in bodily fluids, which might be used to detect human health issues. Uric acid (UA) is a crucial indicator of a high relationship with gout, hyperuricemia, and Lesch–Nyhan syndrome. Therefore, developing a wearable device to noninvasively monitor the UA levels in sweat has drawn enormous attention. In this work, boron-doped graphene quantum dots anchored to carbon nanotubes (BGQDs/CNTs) were proposed as noble-metal-free electrocatalysts for the design of the enzyme-free wearable sensors to monitor the concentration of UA in human sweat. BGQDs could provide extra active sites to enhance the electrocatalytic ability of the UA oxidation reaction. From the results, BGQDs/CNTs exhibit ultrahigh sensitivity of 8.92 ± 0.22 μA μM–1 cm–2 for UA detection compared to pristine CNTs (4.24 ± 0.24 μA μM–1 cm–2). Moreover, density functional theory calculations indicate that B atoms can strengthen the UA molecule adsorption and enlarge electron transfer from the UA molecule to the B-doped graphene sheet, supporting the high sensitivity of BGQDs for UA detection. Hence, this study offers a promising electrocatalyst for using an enzyme-free electrochemical UA sensor with a dependable and steady performance to further the use of wearable electronics.

Regulating the spin density of CoIIIusing boron-doped carbon dots for enhanced electrocatalytic nitrate reduction

“…2e). 28 On the basis of the above analysis, the valence electron configurations of Co with and without BCDs in Co 3 O 4 are identified. Typically, as illustrated in Fig.…”

Graphene and Its Derivatives: Synthesis and Application in the Electrochemical Detection of Analytes in Sweat

“…The primary physiologically significant indicators and their dynamic concentration levels in human sweat are listed in Table 4 . Sweat contains substantial concentrations of lactate [ 282 , 283 , 284 , 285 ], glucose [ 286 , 287 , 288 , 289 , 290 ], uric acid [ 291 , 292 ], ascorbic acid [ 293 , 294 , 295 ], cortisol [ 296 , 297 ], tyrosine [ 298 , 299 ], ethyl glucuronide [ 300 ], F17464 [ 301 ], Na + [ 302 , 303 , 304 , 305 ], Cl − [ 306 , 307 ], K + [ 308 , 309 ], pH [ 310 , 311 , 312 ], NH 4+ [ 313 ], Ca 2+ [ 314 ], Zn 2+ [ 315 ] and Cd 2+ [ 316 ]. Because of their high sensitivity and ease of development in small electronic circuits, the majority of sweat sensors use amperometric and potentiometric transduction methods.…”

“…Because of their high sensitivity and ease of development in small electronic circuits, the majority of sweat sensors use amperometric and potentiometric transduction methods. For different sweat sensing applications, sensitive voltammetric approaches such as SWASV (square wave anodic stripping voltammetry) and DPV (differential pulse voltammetry) have recently been used [ 291 ]. The secretion mechanisms and analyte partition methods in the sweat fluid are linked to the amount of sweat components [ 317 ].…”

Fe Single-Atom Nanozyme-Modified Wearable Hydrogel Patch for Precise Analysis of Uric Acid at Rest

“…Nyein et al developed wearable patches to detect resting sweat pH, Cl – , and l -dopamine for continuous and autonomous monitoring of body physiology at rest; Zhao et al analyzed stress biomarkers (cortisol, Mg 2+ , and pH) in resting sweat by integrating a wearable sweat sensing patch for diagnostic studies of psychological stress; Saha et al developed a lactate transient sensor under low sweat secretion to continuously monitor sweat lactate changes. Similarly, the increase of the sweat uric acid (UA) level is related to the occurrence and progression of metabolic syndrome, obesity, diabetes, coronary heart disease, and other diseases. , However, most of the current wearable sensors for UA detection are tested in exercise sweat, − and there is a lack of sensors that can detect UA in resting sweat.…”