An Enzyme-Free Signal Amplification Technique for Ultrasensitive Colorimetric Assay of Disease Biomarkers
An Enzyme-Free Signal Amplification Technique for Ultrasensitive Colorimetric Assay of Disease Biomarkers
复制标题
一种用于疾病生物标志物超灵敏比色测定的无酶信号放大技术
DOI：
10.1021/acsnano.6b08232
复制
发表时间：
2017-02-01
期刊：
影响因子：
17.1
通讯作者：
Xia, Xiaohu
中科院分区：
文献类型：
--
作者：
Ye, Haihang;Yang, Kuikun;Xia, Xiaohu
基于酶的比色测定法已广泛用于研究实验室和临床诊断数十年。然而，由于受到酶性能的限制，近年来它们的检测灵敏度没有得到实质性的提高，这抑制了许多关键应用，例如癌症的早期检测。在这项工作中，我们展示了一种无酶的信号放大技术，基于封装有Pd-Ir纳米粒子作为过氧化物酶模拟物的金囊泡，用于显着增强灵敏度的疾病生物标志物的比色测定。由于过氧化物酶模拟物的上级催化效率以及这些模拟物的有效装载和释放，该技术克服了酶的固有限制。使用人前列腺表面抗原作为模型生物标志物，我们证明了无酶测定法可以达到femtogram/mL水平的检测限，当使用相同的抗体和类似的程序时，该检测限比传统的基于酶的测定法低10（3）倍以上。
Enzyme-based colorimetric assays have been widely used in research laboratories and clinical diagnosis for decades. Nevertheless, as constrained by the performance of enzymes, their detection sensitivity has not been substantially improved in recent years, which inhibits many critical applications such as early detection of cancers. In this work, we demonstrate an enzyme-free signal amplification technique, based on gold vesicles encapsulated with Pd-Ir nanoparticles as peroxidase mimics, for colorimetric assay of disease biomarkers with significantly enhanced sensitivity. This technique overcomes the intrinsic limitations of enzymes, thanks to the superior catalytic efficiency of peroxidase mimics and the efficient loading and release of these mimics. Using human prostate surface antigen as a model biomarker, we demonstrated that the enzyme-free assay could reach a limit of detection at the femtogram/mL level, which is over 10(3)-fold lower than that of conventional enzyme-based assay when the same antibodies and similar procedure were used.