Simultaneous Voltammetric Determination of Uric Acid, Xanthine, and Hypoxanthine Using CoFe<sub>2</sub>O<sub>4</sub>/Reduced Graphene Oxide-Modified Electrode

<div>Effects of the amount of CoFe<sub>2</sub>O<sub>4</sub>/rGO on the GCE on the anodic peak currents (<span class="nowrap"><svg height="14.0004pt" id="M16" style="vertical-align:-5.3645pt" version="1.1" viewbox="-0.0498162 -8.6359 10.1207 14.0004" width="10.1207pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M405 650H141L135 622C222 616 230 610 215 535L133 116C118 41 113 33 29 28L23 0H289L295 28C209 33 205 40 219 116L298 535C312 609 317 616 399 622L405 650Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,4.719,3.132)"><path d="M169 380V459C122 440 66 423 24 416V392C86 384 90 382 90 317V-135C90 -201 81 -207 17 -213V-240H253V-213C176 -207 169 -201 169 -125V6C182 -1 208 -11 238 -12C368 12 487 109 487 260C487 358 421 449 310 449C298 449 279 444 261 433L169 380ZM169 346C196 367 237 389 269 389C341 389 403 329 403 221C403 109 347 37 263 37C228 37 191 53 169 76V346Z"></path></g></svg>)</span> of <svg 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d="M412 140C382 77 369 73 315 73H129L270 222C362 320 402 379 402 466C402 571 322 635 234 635C177 635 130 609 99 576L42 495L64 475C90 514 133 568 201 568C274 568 318 519 318 435C318 349 255 267 193 193C144 135 87 78 32 23V0H405C417 45 427 89 440 131L412 140Z"></path></g><g transform="matrix(.013,0,0,-0.013,118.987,0)"><path d="M528 54L331 254L528 455L492 493L294 291L96 493L60 455L257 254L60 54L96 16L294 217L492 16L528 54Z"></path></g><g transform="matrix(.013,0,0,-0.013,129.524,0)"><path d="M384 0V27C293 34 287 42 287 114V635C232 613 172 594 109 583V559L157 557C201 555 205 550 205 499V114C205 42 199 34 109 27V0H384Z"></path></g><g transform="matrix(.013,0,0,-0.013,135.764,0)"><path d="M241 635C89 635 35 457 35 312C35 153 89 -12 240 -12C390 -12 443 166 443 312C443 466 390 635 241 635ZM238 602C329 602 354 454 354 312C354 172 330 22 240 22C152 22 124 173 124 313S148 602 238 602Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,142.05,-5.741)"><path d="M556 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Other conditions are as in Figure <a href="../fig8/">8</a>.</div>

Journal of Nanomaterials

fig9

Figure 9

Figure 9: Simultaneous Voltammetric Determination of Uric Acid, Xanthine, and Hypoxanthine Using CoFe<sub>2</sub>O<sub>4</sub>/Reduced Graphene Oxide-Modified Electrode 

Journal of Nanomaterials

Simultaneous Voltammetric Determination of Uric Acid, Xanthine, and Hypoxanthine Using CoFe2O4/Reduced Graphene Oxide-Modified Electrode

Figure 9

Simultaneous Voltammetric Determination of Uric Acid, Xanthine, and Hypoxanthine Using CoFe₂O₄/Reduced Graphene Oxide-Modified Electrode