Li Dachao, Lu Bingyu, Zhu Rui, Yu Haixia, Xu Kexin
State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University , Tianjin, China.
Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin University , Tianjin, China.
Biomicrofluidics. 2016 Feb 26;10(1):011913. doi: 10.1063/1.4942946. eCollection 2016 Jan.
The traditional technology of glucose monitoring is painful and invasive because of the frequent blood collection. Nowadays, the enzyme electrode sensor is mainly used for continuous glucose monitoring in clinic, but it has inherent disadvantages of significant signal drift of current due to bioelectricity in body and the missing of hypoglycemia resulting from the irreversible consumption of glucose at the process of enzyme catalytic reaction. Interstitial fluid (ISF) transdermal extraction can be nearly unsensible which effectively reduces the pain caused by invasive detection so that it may provide a new way to monitor glucose. MEMS technology has been used to produce devices for transdermal ISF extraction, but there is a lack of on-chip ISF volume measurement capabilities, which are required to compensate skin permeability variations. This paper presents a lab-on-a-chip system for ISF transdermal extraction, ISF volume measurement, and optical glucose sensing towards the application of continuous glucose monitoring. The device significantly incorporates a MEMS volume sensor, which measures extracted ISF volume via conductance monitoring, and integrates a fiber-optic surface plasmon resonance sensor to measure glucose concentration in microchannel. The fiber-based technique provides an excellent approach to overcome the above two drawbacks of the enzyme electrode based glucose sensing. Six different volumes were tested, and the standard deviation of every sample is less than 0.05 μl, The resonance wavelength moves from 549.081 nm to 592.914 nm while the concentration ranges from 0 to 200 mg/dl. The feasibility of the single-chip device for accurate and continuous monitoring of subcutaneous ISF glucose concentrations is verified.
传统的血糖监测技术由于频繁采血而具有痛苦和侵入性。如今，酶电极传感器主要用于临床连续血糖监测，但它存在固有缺点，即由于体内生物电导致电流信号显著漂移，以及在酶催化反应过程中葡萄糖不可逆消耗导致低血糖漏检。组织间液（ISF）经皮提取几乎无感知，可有效减轻侵入性检测带来的疼痛，从而可能为血糖监测提供一种新方法。微机电系统（MEMS）技术已被用于生产经皮ISF提取装置，但缺乏片上ISF体积测量能力，而这是补偿皮肤渗透性变化所必需的。本文提出了一种用于ISF经皮提取、ISF体积测量和光学葡萄糖传感的片上实验室系统，以用于连续血糖监测。该装置显著集成了一个MEMS体积传感器，通过电导监测来测量提取的ISF体积，并集成了一个光纤表面等离子体共振传感器来测量微通道中的葡萄糖浓度。基于光纤的技术为克服基于酶电极的葡萄糖传感的上述两个缺点提供了一种出色的方法。测试了六种不同体积，每个样品的标准偏差小于0.05 μl，当浓度范围从0到200 mg/dl时，共振波长从549.081 nm移动到592.914 nm。验证了该单芯片装置准确连续监测皮下ISF葡萄糖浓度的可行性。
