Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo, 192-0397, Japan.
School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan.
Mikrochim Acta. 2023 Dec 13;191(1):24. doi: 10.1007/s00604-023-06108-z.
A novel determination method for protein biomarkers based on on-chip flow rate measurement was developed using a microchip with organic photodiodes (OPDs). This quantitative method is based on the flow rate measurement of an ink solution pushed out by oxygen gas generated through catalase reaction. The amount of oxygen gas generated in the sample reservoir is dependent on the concentration of the analyte; therefore, the flow rate of the ink solution is also dependent on the concentration of the analyte. The concentration of the analyte can thus be estimated by measurement of the ink solution flow rate. The ink solution flow rate was estimated by measuring the migration time of the ink solution between two points using two OPDs placed below the microchannel. The principle of this method was demonstrated by the measurement of catalase using the microchip. In addition, the developed method was applied to the determination of C-reactive protein (CRP), a biomarker of inflammation, based on a catalase-linked immunosorbent assay (C-LISA). The limit of detection for CRP was 0.20 µg/mL. The method was also applied to the determination of CRP in human serum, and the quantitative values obtained by this method were in excellent agreement with those obtained by the conventional enzyme-linked immunosorbent assay (ELISA) method. The developed method does not require a photodetector with high sensitivity and is thus capable of downsizing; therefore, this will be useful for on-site analyses such as point-of-care testing and field measurements.
基于芯片上的流速测量，开发了一种使用带有有机光电二极管（OPD）的微芯片的新型蛋白质生物标志物测定方法。这种定量方法基于通过过氧化氢酶反应产生的氧气推动的墨水流速的测量。样品室中产生的氧气量取决于分析物的浓度；因此，墨水流速也取决于分析物的浓度。因此，可以通过测量墨水流速来估计分析物的浓度。通过在微通道下方放置的两个 OPD 测量墨水流经两点之间的迁移时间来估计墨水流速。使用微芯片测量过氧化氢酶证明了该方法的原理。此外，该方法还应用于基于酶联免疫吸附测定（C-LISA）的炎症标志物 C-反应蛋白（CRP）的测定。CRP 的检测限为 0.20μg/mL。该方法还应用于人血清中 CRP 的测定，该方法得到的定量值与传统酶联免疫吸附测定（ELISA）方法得到的定量值非常吻合。所开发的方法不需要具有高灵敏度的光电探测器，因此能够缩小尺寸；因此，这将有助于现场分析，如即时检测和现场测量。
