应用微生物传感器测定甲醛  

Determination of Formaldehyde with Microbial Biosensor

作　　者：崔建升[1] 汤鸿雁[1] 

机构地区：[1]河北科技大学环境科学与工程学院,石家庄050018

出　　处：《理化检验（化学分册）》2011年第2期144-146,149,共4页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：河北省环境工程重点学科资金资助

摘　　要：将培养好的枯草芽孢杆菌与一定量辅料混合,将其涂布并夹入两片微孔纤维膜之间制成固定化微生物膜。将此微生物膜装在溶解氧电极的阴极(金电极)端面的聚四氟乙烯薄膜上,并使之固定即完成微生物传感器的组装。为测验此传感器对甲醛的响应,按方法的给定条件进行操作,记录加入含甲醛试液前后仪器的输出电流。有甲醛存在时,由于其与微生物之间的同化作用导致一定量氧消耗而使输出电流it与基线电流i0相比明显下降,且其下降程度Δi(i0-it)与甲醛质量浓度在0.005～0.20 g.L-1之间呈线性关系。在甲醛质量浓度为0.1 g.L-1条件下做精密度试验,测得其信号值的相对标准偏差(n=10)为1.13%。用标准加入法试验了方法的回收率,3次试验的平均回收率为107%。又经试验,所制备的干微生物固化膜在4℃冰箱中冷藏,可保存60d仍有效。To prepare immobilized microbial membrane,the selected fungus of Bacillus subtilis was cultured,and after mixing with a definite amount of supplementary,was applied and sandwiched between 2 pieces of micro-porous cellulose membranes.Assembly of the microbial biosensor detector system for formaldehyde（HCHO） was achieved by association of the immobilized microbial membrane with the dissolved oxygen electrode through attaching and fixing the microbial membrane onto the Au-cathode of the oxygen electrode.To test for response of the biosensor to HCHO,values of out-put current i0（base-line current） and it（current-decreased after addition of sample solution containing HCHO） were taken,and it was found that values of Δi（i0-it） kept linear relationship with concentration of HCHO in the range from 0.005 to 0.20 g·L-1.Precision was tested with 0.1 g·L-1 of HCHO,value of RSD（n=10） for the response signals was found to be 1.13%.Recovery was tested by standard addition method,giving average recovery of 107%.It was also found that the dried immobilized microbial membrane kept its efficiency for at least 60d when stored in refrigerator at 4 ℃.

关 键 词：微生物传感器 溶解氧电极 枯草芽孢杆菌 甲醛 

分 类 号：O657.1[理学—分析化学]