Padmanabhan Swathi, Shashank Sarikonda Aryan, Srinivasan Rajesh, Prakash Jaya
IEEE Trans Biomed Eng. 2025 May 5;PP. doi: 10.1109/TBME.2025.3566940.
Glucose sensing in deep tissue is challenging due to high light scattering and the optical properties of tissue constituents.
We present a novel approach that integrates polarized light with optoacousto-fluidics based glucose sensing.
A custom microfluidic chip mimicking blood vessel dimensions was developed to measure optical rotation via optoacoustic detection using polarized light (vertical and circular) at 1560 nm (near-infrared). The system reduces sample volume requirements while maintaining high sensitivity and accuracy. Experiments were performed using serum-like and human blood samples at a depth of 2 mm through whole blood. Flow dynamics was varied to assess their impact on measurement accuracy. Proof-of-concept studies included samples from diabetic and healthy volunteers.
Depth-resolved optoacoustic signals enabled accurate optical rotation quantification for glucose detection. Variations in flow velocity showed no significant effect, confirming system reliability under dynamic conditions. The system achieved a detection limit of 50 mg/dL in serum samples. Classification of diabetic and healthy samples reached an 88% prediction accuracy.
This work demonstrates a low-volume, high-sensitivity method for glucose detection using polarized light and optoacousto-fluidics, with potential for real-time, non-invasive monitoring at tissue depths of 2-3 mm. It lays the foundation for advancing optical rotation-based glucose detection methodologies with significant implications for in-vivo sensing (at depths of 2-3 mm in skin).
由于高光散射和组织成分的光学特性，在深层组织中进行葡萄糖传感具有挑战性。
我们提出了一种将偏振光与基于光声流体的葡萄糖传感相结合的新方法。
开发了一种模仿血管尺寸的定制微流控芯片，通过在1560 nm（近红外）处使用偏振光（垂直偏振光和圆偏振光）进行光声检测来测量旋光度。该系统在保持高灵敏度和准确性的同时降低了样品体积要求。使用血清样和人类血液样本在全血2 mm深度处进行实验。改变流动动力学以评估其对测量准确性的影响。概念验证研究包括来自糖尿病患者和健康志愿者的样本。
深度分辨光声信号能够对葡萄糖检测进行准确的旋光度定量。流速变化显示无显著影响，证实了系统在动态条件下的可靠性。该系统在血清样本中的检测限达到50 mg/dL。糖尿病样本和健康样本的分类预测准确率达到88%。
这项工作展示了一种使用偏振光和光声流体技术进行葡萄糖检测的低体积、高灵敏度方法，具有在2-3 mm组织深度进行实时、无创监测的潜力。它为推进基于旋光度的葡萄糖检测方法奠定了基础，对体内传感（在皮肤2-3 mm深度）具有重要意义。
