High-sensitive biochemical gas sensor based on the gas-biomolecule interaction

研制了一种以NADH为电子受体的生物传感器。该生物传感器通过NADH的荧光来测量底物的存在。为了提高对甲醛的敏感性，对NADH进行了化学放大研究。乙醛脱氢酶在NAD+存在下氧化甲醛生成甲酸和NADH。我们共固定化甲酸脱氢酶，利用甲酸再生NADH。因此，该传感器对甲缩醛显示出亚ppb级别的灵敏度。并利用光催化TiO2光催化剂进行了实际样品测试。该传感器利用光催化反应的效应，成功地实时跟踪甲醛的变化。

A biosensor using NADH as an electron acceptor was developed. The biosensor measures the presence of the substrate as fluorescence of NADH. In order to enhance the sensitivity to formaldehyde, chemical amplification of NADH was investigated. Aldehyde dehydrogenase produces formic acid and NADH by oxidizing formaldehyde under the presence of NAD+. We co-immobilized formic acid dehydrogenase to re-produce NADH using formic acid. Consequently, the sensor showed sub-ppb level sensitivity to forimaldehyde. Also, real-sample test using photocatalystic TiO2 was carried out. The sensor successfully traced the change of formaldehyde by the effect of photocatalystic reaction in real-time.