Ben Ali M, Gonchar M, Gayda G, Paryzhak S, Maaref M A, Jaffrezic-Renault N, Korpan Y
Institut Supérieur des Sciences, Appliquées et de Technologies de Sousse, Cité Taffela , Ibn Khaldoun, 4003, Sousse Tunisia.
Biosens Bioelectron. 2007 Jun 15;22(12):2790-5. doi: 10.1016/j.bios.2006.10.002. Epub 2006 Nov 13.
A new formaldehyde-selective biosensor was constructed using NAD(+)- and glutathione-dependent recombinant formaldehyde dehydrogenase as a bio-recognition element immobilised on the surface of Si/SiO(2)/Si(3)N(4) structure. Sensor's response to formaldehyde was evaluated by capacitance measurements. The calibration curves obtained for formaldehyde concentration range from 10 microM to 20mM showed a broad linear response with a sensitivity of 31 mV/decade and a detection limit about 10 microM. It has been shown that the output signal decreases with the increase of borate buffer concentration and the best sensitivity is observed in 2.5mM borate buffer, pH 8.40. The response of the created formaldehyde-sensitive biosensor has also been examined in 2.5mM Tris-HCl buffer, and the shift to the positive bias of the C(V) curves along with the potential axis has been observed, but the sensitivity of the biosensor in this buffer is decreased dramatically to the value of 2.4 mV/decade.
利用固定在Si/SiO₂/Si₃N₄结构表面的烟酰胺腺嘌呤二核苷酸（NAD⁺）和谷胱甘肽依赖性重组甲醛脱氢酶作为生物识别元件，构建了一种新型的甲醛选择性生物传感器。通过电容测量评估传感器对甲醛的响应。在10微摩尔至20毫摩尔的甲醛浓度范围内获得的校准曲线显示出宽泛的线性响应，灵敏度为31毫伏/十倍浓度变化，检测限约为10微摩尔。结果表明，输出信号随硼酸盐缓冲液浓度的增加而降低，在pH 8.40的2.5毫摩尔硼酸盐缓冲液中观察到最佳灵敏度。还在2.5毫摩尔三羟甲基氨基甲烷盐酸盐（Tris-HCl）缓冲液中检测了所制备的甲醛敏感生物传感器的响应，观察到C(V)曲线沿电位轴正向偏移，但该缓冲液中生物传感器的灵敏度急剧下降至2.4毫伏/十倍浓度变化。
