Department of Bioengineering, Santa Clara University, Santa Clara, CA, USA.
Lab Chip. 2018 Nov 6;18(22):3471-3483. doi: 10.1039/c8lc00758f.
Wearable technologies have potential to transform healthcare by providing continuous measurements of physiological parameters. Sensors that passively monitor physiological pressure without using electronic components are ideal for wearable contact lenses because they are easy to interface with the cornea and the external environment. Here, we report a passive integrated microfluidic sensor with a novel transduction mechanism that converts small strain changes into a large fluidic volume expansion, detectable by a smart-phone camera. The optimization of the sensor architecture and material properties results in a linear and stable sensor response. We have shown that the sensor has a detection limit of <0.06% for uniaxial and <0.004% for biaxial strain. We embedded our sensor in silicone contact lenses and measured the intraocular pressure induced strain in porcine eyes in the physiological range. The sensor's continuous operation capability for >19 hours and a lifetime reaching >7 months demonstrate its potential for long-term ophthalmic monitoring applications.
可穿戴技术有潜力通过提供生理参数的连续测量来改变医疗保健。被动监测生理压力而不使用电子元件的传感器非常适合用于可穿戴隐形眼镜，因为它们易于与角膜和外部环境接口。在这里，我们报告了一种具有新颖转换机制的被动集成微流传感器，该传感器将小应变变化转换为可通过智能手机摄像头检测的大流体体积膨胀。传感器结构和材料特性的优化导致传感器响应呈线性和稳定。我们已经表明，该传感器对单轴应变的检测极限<0.06%，对双轴应变的检测极限<0.004%。我们将传感器嵌入硅酮隐形眼镜中，并在生理范围内测量了猪眼的眼压诱导应变。传感器的连续运行能力超过 19 小时，寿命超过 7 个月，这证明了它在长期眼科监测应用中的潜力。
