基于多壁碳纳米管的三电极血乙醇生物传感器的研究

Three Electrodes Biosensor for Alcohol in Whole Blood Based on Multi-wall Carbon-nanotube

采用丝网印刷技术在PVC基板上印制三电极,将多壁碳纳米管、麦尔多拉蓝、乙醇脱氢酶(ADH)以及氧化型辅酶Ⅰ(NAD+)依次修饰在工作电极表面,然后在该三电极表面贴一层亲水膜,形成一个5μL反应池,制成血乙醇检测新型生物传感器检测条。结果表明,此生物传感器具有良好的准确性和稳定性;检测线性范围为0.5～20mmol/L,r=0.99493;检出限为0.22mmol/L;电流达到95%稳态时间小于15s。考察了pH值、温度及干扰物对生物传感器的影响。用此生物传感器和顶空气相色谱法对10份全血标本乙醇浓度平行测试,两者相关性良好r=0.97583。利用虹吸现象吸取微量全血直接定量测定乙醇浓度是此生物传感器的特点。

A novel disposable three electrodes blood alcohol biosensor strip was fabricated by a screen printing technique. Multi-wall carbon nanotube（ MWCNT） ,Meldola′s（ MB） ,alcohol dehydrogenase（ ADH） and nicotinamide adenine dinucleotide cofactor （ NAD ＋ ） were modified on the surface of the carbon working electrode. Then hydrophilic membrane was stuck in the outermost of the three electrodes to make a reaction camera of 5 μL. Experimental results indicated that the biosensor possessed good accuracy and stability,the linear response range was 0. 5-20 mmol/L with correlation coefficient of 0. 9949, detection limit was 0. 22 mmol/L,and the response time was less than 15 s. Some influencing factors to the biosensor were investigated,such as the pH,temperature and interferences. Correlation analysis showed that there was a significant correlation between the methods of biosensor and the headspace vapor phase chromatography in 10 whole blood samples （ r = 0. 97583） . Small volume whole blood sucked using siphonage to detect blood alcohol directly and quantitatively was the obvious character of the biosensor.