Escola Politécnica, Universidade de São Paulo, São Paulo 05508-010, Brazil.
Sensors (Basel). 2022 Apr 24;22(9):3265. doi: 10.3390/s22093265.
A label-free, sensitive, miniaturized sensing device was developed for detecting living cells in their flow stream. The outstanding performance of this biosensor in distinguishing living cells in cell suspension was achieved by integrating microstrip stub resonator above a microfluidic structure using the metallic nanowire-filled membrane technology. The cell suspension flows in a microfluidic channel placed between the tip of the stub resonator and its ground plane as the substrate to take advantage of the uniform and concentrated field distribution. We studied the changes in relative permittivity due to the presence of a single living cell in the phase of the transmitted signal (S). An average variation of as much as 22.85 ± 1.65° at ~11.1 GHz is observed for the living cell sensing using this optimized device. This biosensor could detect rapid flowing cells in their biological medium in real-time and hence, can be used as an early diagnosis and monitoring tool for diseases.
我们开发了一种无标记、敏感、微型化的传感设备，用于在其流动流中检测活细胞。通过使用金属纳米线填充膜技术，在微流控结构上方集成微带短截线谐振器，该生物传感器在区分细胞悬浮液中的活细胞方面表现出色。细胞悬浮液在微流道中流动，微流道位于短截线谐振器的尖端与其接地平面之间的基板上，以利用均匀和集中的场分布。我们研究了由于单个活细胞存在而导致的传输信号（S）相位中相对介电常数的变化。使用这种优化的设备进行活细胞感应，观察到平均变化高达 22.85 ± 1.65°，在约 11.1 GHz。这种生物传感器可以实时检测其生物介质中快速流动的细胞，因此可作为疾病的早期诊断和监测工具。
