Development of an Immunoassay for the Detection of Amyloid Beta 1-42 and Its Application in Urine Samples

<div>Development of A<i>β</i>1-42 detection. (a) Indirect ELISA calibration curves for A<i>β</i>1-42 using 1 : 1,000 (v/v) dilution of alpaca antiserum. (b) Optimization of coating antigen using indirect competitive ELISA. The percent binding showed a competition percentage of 6 concentrations of competitive A<i>β</i>1-42 (62, 125, 250, 500, 1,000, and 2,000 ng/ml) to a 1 : 1,000 (v/v) dilution of alpaca antiserum at 3 concentrations of coating antigen (<span class="nowrap"><svg height="9.92533pt" id="M9" style="vertical-align:-1.57651pt" version="1.1" viewbox="-0.0498162 -8.34882 52.8904 9.92533" width="52.8904pt" 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="M540 9V501H48V9H540Z"></path></g><g transform="matrix(.013,0,0,-0.013,11.263,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z"></path></g><g transform="matrix(.013,0,0,-0.013,22.526,0)"><path 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 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238 602Z"></path></g></svg>,</span> <span class="nowrap"><svg height="9.92533pt" id="M10" style="vertical-align:-1.57651pt" version="1.1" viewbox="-0.0498162 -8.34882 53.9865 9.92533" width="53.9865pt" 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="M651 2L336 538H334L19 2L21 0H649L651 2Z"></path></g><g transform="matrix(.013,0,0,-0.013,12.355,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z"></path></g><g transform="matrix(.013,0,0,-0.013,23.618,0)"><path d="M285 378C315 398 338 416 353 432C373 451 384 474 384 503C384 579 325 635 236 635H235C182 635 136 610 108 579L65 516L85 496C110 533 150 575 205 575C258 575 300 543 300 481C300 407 232 369 141 339L147 310C163 315 188 321 211 321C268 321 338 284 338 192C338 94 288 40 217 40C160 40 119 68 93 91C85 98 77 97 69 91C60 84 47 71 46 58C44 46 48 35 62 22C75 10 116 -12 162 -12C234 -12 424 62 424 224C424 297 373 359 285 376V378Z"></path></g><g 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602Z"></path></g></svg>,</span> and <svg height="9.92533pt" id="M11" style="vertical-align:-1.57651pt" version="1.1" viewbox="-0.0498162 -8.34882 53.9865 9.92533" width="53.9865pt" 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="M651 538L649 540H21L19 538L334 2H336L651 538Z"></path></g><g transform="matrix(.013,0,0,-0.013,12.355,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z"></path></g><g transform="matrix(.013,0,0,-0.013,23.618,0)"><path d="M456 178V225H360V632H320C217 496 115 347 20 206V178H280V106C280 40 276 34 189 27V0H445V27C364 34 360 39 360 106V178H456ZM280 225H82C149 335 214 431 278 520H280V225Z"></path></g><g transform="matrix(.013,0,0,-0.013,29.858,0)"><path d="M95 130C70 130 46 113 46 88C46 72 54 64 59 64C93 55 121 33 121 -3C121 -41 93 -68 44 -88L55 -117C117 -98 186 -56 186 22C186 91 131 130 95 130Z"></path></g><g transform="matrix(.013,0,0,-0.013,35.001,0)"><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(.013,0,0,-0.013,41.241,0)"><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(.013,0,0,-0.013,47.481,0)"><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></svg> ng/ml of A<i>β</i>1-42 in coating buffer). (c) ic-competitive ELISA calibration curves for A<i>β</i>1-42 using a 1 : 1000 (v/v) dilution of alpaca antiserum. The calibration curve was obtained using analyte standards prepared in PBS buffer. (d) ic-competitive ELISA calibration curves obtained by OD.</div>

Journal of Immunology Research

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Figure 1

Figure 1: Development of an Immunoassay for the Detection of Amyloid Beta 1-42 and Its Application in Urine Samples 