Department of Chemistry, Institute for Genomic Biology, and Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Anal Chem. 2009 Nov 15;81(22):9499-506. doi: 10.1021/ac902006p.
Recent advances in label-free biosensing techniques have shown the potential to simplify clinical analyses. With this motivation in mind, this paper demonstrates for the first time the use of silicon-on-insulator microring optical resonator arrays for the robust and label-free detection of a clinically important protein biomarker in undiluted serum, using carcinoembryonic antigen (CEA) as the test case. We utilize an initial-slope-based quantitation method to sensitively detect CEA at clinically relevant levels and to determine the CEA concentrations of unknown samples in both buffer and undiluted fetal bovine serum. Comparison with a commercial enzyme-linked immunosorbent assay (ELISA) kit reveals that the label-free microring sensor platform has a comparable limit of detection (2 ng/mL) and superior accuracy in the measurement of CEA concentration across a 3 order of magnitude dynamic range. Notably, we report the lowest limit of detection to date for a microring resonator sensor applied to a clinically relevant cancer biomarker. Although this report describes the robust biosensing capabilities of silicon photonic microring resonator arrays for a single parameter assay, future work will focus on utilizing the platform for highly multiplexed, label-free bioanalysis.
近年来，无标记生物传感技术的进展显示出简化临床分析的潜力。基于这一动机，本文首次展示了使用绝缘体上硅微环光学谐振器阵列在未稀释的血清中对临床重要的蛋白质生物标志物进行稳健、无标记检测的方法，以癌胚抗原（CEA）作为检测案例。我们利用基于初始斜率的定量方法，以临床相关水平灵敏地检测 CEA，并确定缓冲液和未稀释胎牛血清中未知样品的 CEA 浓度。与商业酶联免疫吸附测定（ELISA）试剂盒的比较表明，无标记微环传感器平台在检测 CEA 浓度的 3 个数量级动态范围内具有可比的检测限（2ng/mL）和更高的准确性。值得注意的是，我们报告了迄今为止应用于临床相关癌症生物标志物的微环谐振器传感器的最低检测限。尽管本报告描述了硅光子微环谐振器阵列在单一参数测定中的强大生物传感能力，但未来的工作将集中于利用该平台进行高度多重、无标记的生物分析。
