Theoretical and experimental analysis of analyte transport in a fiber-optic, Protein C immuno-biosensor
Theoretical and experimental analysis of analyte transport in a fiber-optic, Protein C immuno-biosensor
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DOI：
10.1002/bit.20310
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发表时间：
2004-12-30
影响因子：
3.8
通讯作者：
Kang, KA
中科院分区：
文献类型：
--
作者：
Tang, L;Kwon, HJ;Kang, KA
蛋白C （Protein C， PC）是人体血浆中一种重要的抗凝剂，早期诊断缺乏蛋白C对预防危险的血栓栓塞并发症至关重要。本课课组正在研制一种用于PC缺乏症实时诊断的光纤PC免疫生物传感器。该传感器对缓冲溶液中PC的定量具有良好的灵敏度和特异性。然而，对于等离子体样品，由于样品反应时间有限，传感器产生的信号强度仅为缓冲液中PC的30%。推测高等离子体粘度（1.9 cP）是信号强度降低的主要原因。在本研究中，光纤PC生物传感器的传感性能根据样品介质的物理和化学性质进行了系统的表征。理论和实验分析表明，PC分子在粘性样品中的扩散速率降低导致传感系统的传质受限。在免疫反应过程中，样品/试剂溶液的对流流动可以增加分析物质量从整体溶液到传感器表面的传输速率，随着流速的增加，反应动力学从传质受限变为反应受限。结果表明，对流等离子体样品显著提高了PC传感器的性能。系统分析了样品和试剂的流速和孵育时间对传感器性能的影响，以优化PC传感的检测方案。目前，一个6厘米长的免疫生物传感器能够在5分钟内定量血浆（1ml）中杂合PC缺乏范围（0.5至2.5马克杯/毫升）中的PC，平均信噪比为50。(C) 2004 Wiley期刊有限公司
Protein C (PC) is an important anticoagulant in human blood plasma, and early diagnosis of PC deficiency is critical for preventing dangerous thromboembolic complications. A fiber-optic PC immuno-biosensor has been under development in our research group for real-time PC-deficiency diagnosis. The sensor has demonstrated a good sensitivity and specificity for quantifying PC in buffered solutions. However, for plasma samples, with a limited sample reaction time, the sensor produced only 30% of the signal intensity of PC in buffer. The high plasma viscosity (1.9 cP) was speculated as the major reason for signal intensity reduction. In this investigation, the sensing performance of the fiber-optic PC biosensor is systematically characterized in terms of physical and chemical properties of the sample media. Theoretical and experimental analyses indicate that the reduced diffusion rate of PC molecules in viscous samples caused the sensing system to be more mass-transfer-limited. Convective flow of sample/reagent solutions during immunoreactions can increase the rate of the analyte mass transport from the bulk solution to the sensor surface, with reaction kinetics changing from mass-transfer-limited to reaction-limited as flow velocity increases. It was shown that PC sensor performance was significantly improved for plasma samples with convection. The effect of the flow velocity and incubation times for samples and reagents on the sensor performance was also systematically analyzed to optimize the assay protocol for PC sensing. Currently, a 6-cm-long immuno-biosensor is capable of quantifying PC in plasma (1 mL) in the heterozygous PC deficiency range (0.5 to 2.5 mug/mL) within 5 minutes, at an average signal-to-noise ratio of 50. (C) 2004 Wiley Periodicals, Inc.