Many methods for early diagnosis of the disease use biomarker tests, which measure indicators of biological state in body fluids or blood. However, a limitation of these methods is their low sensitivity to biomarkers. In this study, human serum albumin (HSA) based nanoparticles capable of encapsulating excess horseradish peroxidase (HRP) are synthesized and applied to the development of enzyme-linked immunosorbent assay (ELISA) kit with ultra-high sensitivity. The size of the nanoparticles and the amount of encapsulated enzyme are controlled by varying the synthesis conditions of pH and protein concentration, and the surface of the nanoparticles is modified with protein A (proA) to immobilize antibodies to the nanoparticles by self-assembly. Using the synthesized nanoparticles, the biomarker of breast cancer, thioredoxin-1, can be measured in the range of 10 fM to 100 pM by direct sandwich ELISA, which is 105 times more sensitive than conventional methods.

中文翻译：

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酶包裹人血清白蛋白纳米粒子的超灵敏ELISA检测硫氧还蛋白-1

用于疾病早期诊断的许多方法都使用生物标志物测试，该测试可测量体液或血液中生物状态的指标。但是，这些方法的局限性在于它们对生物标志物的敏感性低。在这项研究中，能够包封过量辣根过氧化物酶（HRP）的基于人血清白蛋白（HSA）的纳米颗粒被合成并用于具有超高灵敏度的酶联免疫吸附测定（ELISA）试剂盒的开发。通过改变pH和蛋白质浓度的合成条件来控制纳米粒子的大小和包封的酶的量，并且纳米粒子的表面用蛋白质A（proA）修饰以通过自组装将抗体固定在纳米粒子上。使用合成的纳米粒子，乳腺癌的生物标志物硫氧还蛋白-1，