摘要
基于超滤原理提取组织液、并对其进行后续葡萄糖检测,是实现长期血糖持续监测的一种有效途径.本文提出一种可用于组织液超滤提取及葡萄糖持续检测的传感器微系统.该系统主要由微流控底座和葡萄糖传感器芯片组成.其中微流控底座由PDMS微通道、SU-8单向阀等微加工器件组成,在压力作用下可完成组织液提取及将检测过的组织液排出的功能.采用体硅加工方法制作葡萄糖传感器芯片微型腔体及腔体底部的微孔膜,研制出具有扩散控制功能的三电极检测芯片,并在其上通过琼脂糖包埋方法固定葡萄糖氧化酶、基于电化学原理实现葡萄糖浓度的检测.实验结果表明,该系统可以实现液体的灵活提取,并且葡萄糖检测响应时间小于5 s,在0.4 V工作电压下线性测量范围达0.2～20 mmol/L,灵敏度为9.76 nA/(mmol.L-1),相关系数为0.995 4.多次测量5 mmol/L样本,差异系数3.48%.可见该传感系统具有较好的稳定性,并且体积小、易于集成,有望用于组织液灵活提取及其葡萄糖持续监测.
Considering the demand of long-term blood glucose monitoring, a novel MEMS sensor system was developed, which extracts tissue fluid in vivo by ultrafiltration and monitors glucose in vitro. The construction and properties of this sensor system for tissue fluid ultrafiltration sampling and on-line glucose monitoring were presented. It comprised a glucose sensor chip integrated on the microfluidics base. The microfluidics base consisted of PDMS microchannel and SU-8 check valve fabricated by MEMS technolo- gy. This sensor system could harvest tissue fluid under negative pressure for glucose monitoring and dis- charge the used tissue fluid after each measurement. The 3-electrode glucose sensor chip based on elec- trochemical mechanism was fabricated by silicon processing method, and it had a silicon etched cavity on the top side. Pores were etched into the membrane at the cavity ground, so the sensor chip was provided with diffusion control of the analyte through the membrane into cavity containing agarose immobilised en- zyme. Experimental results show that this system can realize the flexible tissue fluid sampling, and its signal response time at increasing glucose concentrations is 5 s; under the voltage of 0. 4 V the linear range is large enough to cover the required broad area of blood glucose （0. 2--20 mmol / L）, the sensi-tivity is 9.76 nA/（ mmol- L- 1 ） , and the correlation coefficient is 0. 995 4 ; the coefficient of variation for measuring 5 mmoL/L glucose solution is 3.48% . It can be seen that the glucose sensor chip has good re- liability and stability, and it can be easily integrated into the sensor system for tissue fluid sampling and subsequent glucose monitoring because of its small dimension.
出处
《纳米技术与精密工程》
CAS
CSCD
2013年第3期202-210,共9页
Nanotechnology and Precision Engineering
基金
国家高技术研究发展计划(863计划)资助项目(2011AA040406)
机器人技术与系统国家重点实验室基金资助项目(HIT)(SKLRS-2010-MS-20)
山东省科技发展计划资助项目(BS2009ZZ018
2010GGX10405)
关键词
血糖检测
组织液
MEMS
传感器
blood glucose monitoring
tissue fluid
MEMS
sensor
