Here, we present integrated nanorod arrays on microfluidic chips for fast and sensitive flow-through immunoassays of physiologically relevant macromolecules. Dense arrays of Au nanorods are easily fabricated through one-step oblique angle deposition, which eliminates the requirement of advanced lithography methods. We report the utility of this plasmonic structure to improve the detection limit of the cardiac troponin I (cTnI) assay by over 6 × 10⁵-fold, reaching down to 33.9 fg mL⁻¹ (~1.4 fM), compared with an identical assay on glass substrates. Through monolithic integration with microfluidic elements, the device enables a flow-through assay for quantitative detection of cTnI in the serum with a detection sensitivity of 6.9 pg mL⁻¹ (~0.3 pM) in <6 min, which was 4000 times lower than conventional glass devices. This ultrasensitive detection arises from the large surface area for antibody conjugation and metal-enhanced fluorescent signals through plasmonic nanostructures. Moreover, due to the parallel arrangement of flow paths, simultaneous detection of multiple cancer biomarkers, including prostate-specific antigen and carcinoembryonic antigen, has been fulfilled with increased signal-to-background ratios. Given the high performance of this assay, together with its simple fabrication process that is compatible with standard mass manufacturing techniques, we expect that the prepared integrated nanorod device can bring on-site point-of-care diagnosis closer to reality.

在这里，我们提出了微流控芯片上的集成纳米棒阵列，用于对生理相关大分子进行快速、灵敏的流通免疫测定。通过一步斜角沉积可以轻松制造密集的金纳米棒阵列，从而无需先进的光刻方法。我们报告了这种等离子体结构的实用性，与相同的检测相比，将心肌肌钙蛋白 I (cTnI) 检测的检测限提高了 6 × 10 ⁵倍以上，低至 33.9 fg mL ^-1 (~1.4 fM)在玻璃基板上。通过与微流体元件的整体集成，该装置可实现血清中 cTnI 的定量检测，检测灵敏度在 6 分钟内达到 6.9 pg mL ⁻¹ (~0.3 pM)，比传统方法低 4000 倍。玻璃设备。这种超灵敏的检测源于抗体偶联的大表面积和通过等离子体纳米结构的金属增强荧光信号。此外，由于流路的平行排列，可以实现多种癌症生物标志物的同时检测，包括前列腺特异性抗原和癌胚抗原，并提高了信号背景比。鉴于该测定的高性能，以及与标准大规模制造技术兼容的简单制造工艺，我们期望所制备的集成纳米棒装置能够使现场护理诊断更接近现实。