Kim Dong Hyung, Chegal Won, Cho Yong Jai, Won O Sang, Van Le Long, Diware Mangesh S, Paek Se-Hwan, Kim Young Dong, Cho Hyun Mo
Division of Interdisciplinary Materials Measurement Institute, Korea Research Institute of Standards and Science, 267 Gajeongno, Yuseong-Gu, Daejeon, 34113, South Korea.
Division of Advanced Instrumentation Institute, Korea Research Institute of Standards and Science, 267 Gajeongno, Yuseong-Gu, Daejeon, 34113, South Korea.
Biosens Bioelectron. 2020 Nov 15;168:112525. doi: 10.1016/j.bios.2020.112525. Epub 2020 Aug 21.
Early diagnosis of acute myocardial infarction (AMI) significantly reduce the mortality rate and can be achieved via high-sensitive detection of AMI specific cardiac troponin I (cTnI) biomarker. Here, we present normal-incident type solution-immersed silicon (NI-SIS) ellipsometric biosensor, designed for ultra-high sensitive, high-throughput, label-free detection of the target protein. The NI-SIS sensors are equipped with a specially designed prism that maintains the angle of incidence close to the Brewster angle during operation, which significantly reduces SIS noise signals induced by the refractive index fluctuations of the surrounding medium, improves the signal-to-noise ratio, in-results lowers the detection limit. We applied NI-SIS biosensor for ultra-sensitive detection of cTnI biomarkers in human serum. The optimized sensor chip fabrication and detection operation procedures are proposed. The wide linear concentration ranges of fg/mL to ng/mL is achieved with the detection limit of 22.0 fg/mL of cTnI. The analytical correlation was assessed by linear regression analysis with the results of the Pathfast reference system. These impressive biosensing capabilities of NI-SIS technology have huge potentials for accurate detection of target species in different application areas, such as diagnosis, drug discovery, and food contaminations.
急性心肌梗死（AMI）的早期诊断可显著降低死亡率，而这可以通过对AMI特异性心肌肌钙蛋白I（cTnI）生物标志物进行高灵敏度检测来实现。在此，我们展示了一种正入射型溶液浸没式硅（NI-SIS）椭圆偏振生物传感器，其设计用于对目标蛋白进行超高灵敏度、高通量、无标记检测。NI-SIS传感器配备了一个特殊设计的棱镜，该棱镜在操作过程中能使入射角保持接近布儒斯特角，这显著降低了由周围介质折射率波动引起的SIS噪声信号，提高了信噪比，进而降低了检测限。我们将NI-SIS生物传感器应用于人血清中cTnI生物标志物的超灵敏检测。提出了优化的传感器芯片制造和检测操作程序。实现了从fg/mL到ng/mL的宽线性浓度范围，cTnI的检测限为22.0 fg/mL。通过线性回归分析并与Pathfast参考系统的结果进行比较，评估了分析相关性。NI-SIS技术这些令人印象深刻的生物传感能力在不同应用领域（如诊断、药物发现和食品污染检测）中对目标物种进行准确检测方面具有巨大潜力。
