Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053, Regensburg, Germany.
Roche Diagnostics GmbH, 68305, Mannheim, Germany.
Anal Bioanal Chem. 2024 Apr;416(10):2411-2422. doi: 10.1007/s00216-024-05223-x. Epub 2024 Mar 8.
Point-of-care sensors targeting blood marker analysis must be designed to function with very small volumes since acquiring a blood sample through a simple, mostly pain-free finger prick dramatically limits the sample size and comforts the patient. Therefore, we explored the potential of converting a conventional lateral flow assay (LFA) for a significant biomarker into a self-contained and compact polymer channel-based LFA to minimize the sample volume while maintaining the analytical merits. Our primary objective was to eliminate the use of sample-absorbing fleece and membrane materials commonly present in LFAs. Simultaneously, we concentrated on developing a ready-to-deploy one-step LFA format, characterized by dried reagents, facilitating automation and precise sample transport through a pump control system. We targeted the detection of the heart failure biomarker NT-proBNP in only 15 µL human whole blood and therefore implemented strategies that ensure highly sensitive detection. The biosensor combines streptavidin-functionalized magnetic beads (MNPs) as a 3D detection zone and fluorescence nanoparticles as signal labels in a sandwich-based immunoassay. Compared to the currently commercialized LFA, our biosensor demonstrates comparable analytical performance with only a tenth of the sample volume. With a detection limit of 43.1 pg∙mL and a mean error of 18% (n ≥ 3), the biosensor offers high sensitivity and accuracy. The integration of all-dried long-term stable reagents further enhances the convenience and stability of the biosensor. This lateral flow channel platform represents a promising advancement in point-of-care diagnostics for heart failure biomarkers, offering a user-friendly and sensitive platform for rapid and reliable testing with low finger-prick blood sample volumes.
即时检测传感器针对血液标志物分析必须设计成能够处理非常小的体积，因为通过简单、基本无痛的指尖采血来获取血液样本会极大地限制样本量并使患者感到舒适。因此，我们探索了将传统的侧向流动分析（LFA）转化为自包含的紧凑型聚合物通道 LFA 的潜力，以最小化样本量，同时保持分析优势。我们的主要目标是消除侧向流动分析中常用的样本吸收羊毛和膜材料的使用。同时，我们专注于开发一种即插即用的一步式 LFA 格式，其特点是干燥试剂，便于通过泵控制系统实现自动化和精确的样本传输。我们的目标是仅检测 15µL 人全血中的心力衰竭生物标志物 NT-proBNP，因此实施了确保高灵敏度检测的策略。该生物传感器将链霉亲和素功能化的磁性珠（MNPs）作为 3D 检测区，并在夹心免疫测定中使用荧光纳米颗粒作为信号标记。与目前商业化的 LFA 相比，我们的生物传感器在仅使用十分之一的样本量的情况下表现出可比的分析性能。该生物传感器的检测限为 43.1pg∙mL，平均误差为 18%（n≥3），具有高灵敏度和准确性。所有干燥的长期稳定试剂的集成进一步增强了生物传感器的便利性和稳定性。这种侧向流动通道平台代表了心力衰竭生物标志物即时检测诊断的一个有前途的进展，提供了一个用户友好且敏感的平台，用于快速可靠的测试，只需用少量指尖采血即可。
