Biosensor Research Team, Electronics and Telecommunications Research Institute, Daejeon 305-700, South Korea.
Anal Chem. 2010 Dec 1;82(23):9686-93. doi: 10.1021/ac101716p. Epub 2010 Nov 4.
Cardiac markers in human serum with concentrations less than 0.1 ng/mL were analyzed by use of a guided-mode resonance (GMR) biosensor. Cardiac troponin I (cTnI), creatine kinase MB (CK-MB), and myoglobin (MYO) were monitored in the serum of both patients and healthy controls. Dose-response curves ranging from 0.05 to 10 ng/mL for cTnI, from 0.1 to 10 ng/mL for CK-MB, and from 0.03 to 1.7 μg/mL for MYO were obtained. The limits of detection (LOD) for cTnI, CK-MB, and MYO were less than 0.05, 0.1, and 35 ng/mL, respectively. Analysis time was 30 min, which is short enough to meet clinical requirements. Antibody immobilization and the hydrophilic properties of the guided-mode resonance filter (GMRF) surface were investigated by X-ray photoelectron spectroscopy (XPS) and by monitoring the peak wavelength shift and water contact angle (CA). Both assays used to evaluate the surface density of the immobilized antibodies, a sandwich enzyme-linked immunosorbent assay (ELISA) and a sandwich immunogold assay, showed that the antibodies were successfully immobilized and sufficiently aligned to detect the low concentration of biomarkers. Our results show that the GMR biosensor will be very useful in developing low-cost portable biosensors that can screen for cardiac diseases.
使用导模共振（GMR）生物传感器分析血清中心脏标志物，其浓度小于 0.1ng/mL。监测了患者和健康对照者血清中的心肌肌钙蛋白 I（cTnI）、肌酸激酶同工酶 MB（CK-MB）和肌红蛋白（MYO）。获得了 cTnI 浓度范围为 0.05 至 10ng/mL、CK-MB 浓度范围为 0.1 至 10ng/mL、MYO 浓度范围为 0.03 至 1.7μg/mL 的剂量反应曲线。cTnI、CK-MB 和 MYO 的检测限（LOD）分别小于 0.05、0.1 和 35ng/mL。分析时间为 30 分钟，足以满足临床需求。通过 X 射线光电子能谱（XPS）和监测峰值波长位移和水接触角（CA）研究了抗体固定化和导模共振滤波器（GMRF）表面的亲水性。两种用于评估固定化抗体表面密度的检测方法，即夹心酶联免疫吸附测定（ELISA）和夹心免疫金测定，均表明抗体已成功固定化且排列充分，可检测到低浓度的生物标志物。我们的研究结果表明，GMR 生物传感器将非常有助于开发用于筛选心脏病的低成本便携式生物传感器。
