An enzymatic biosensor based on nitric oxide reductase (NOR; purified from Marinobacter hydrocarbonoclasticus) was developed for nitric oxide (NO) detection. The biosensor was prepared by deposition onto a pyrolytic graphite electrode (PGE) of a nanocomposite constituted by carboxylated single-walled carbon nanotubes (SWCNTs), a lipidic bilayer [1,2-di-(9Z-octadecenoyl)-sn-glycero-3-phosphoethanolamine (DOPE), 1,2-di-(9Z-octadecenoyl)-3-trimethylammonium-propane (DOTAP), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-polyethylene glycol (DSPE-PEG)] and NOR. NOR direct electron transfer and NO bioelectrocatalysis were characterized by several electrochemical techniques. The biosensor development was also followed by scanning electron microscopy and Fourier transform infrared spectroscopy. Improved enzyme stability and electron transfer (1.96 × 10⁻⁴ cm.s⁻¹ apparent rate constant) was obtained with the optimum SWCNTs/(DOPE:DOTAP:DSPE-PEG)/NOR) ratio of 4/2.5/4 (v/v/v), which biomimicked the NOR environment. The PGE/[SWCNTs/(DOPE:DOTAP:DSPE-PEG)/NOR] biosensor exhibited a low Michaelis-Menten constant (4.3 μM), wide linear range (0.44–9.09 μM), low detection limit (0.13 μM), high repeatability (4.1% RSD), reproducibility (7.0% RSD), and stability (ca. 5 weeks). Selectivity tests towards L-arginine, ascorbic acid, sodium nitrate, sodium nitrite and glucose showed that these compounds did not significantly interfere in NO biosensing (91.0 ± 9.3%–98.4 ± 5.3% recoveries). The proposed biosensor, by incorporating the benefits of biomimetic features of the phospholipid bilayer with SWCNT's inherent properties and NOR bioelectrocatalytic activity and selectivity, is a promising tool for NO.

基于一氧化氮还原酶（NOR酶促生物传感器;从纯化Marinobacter hydrocarbonoclasticus）被开发用于一氧化氮（NO）检测。生物传感器的制备方法是：将脂族双层[1,2-二-（9Z-十八烯酰基）-sn-甘油-3]沉积在由羧基化单壁碳纳米管（SWCNT）构成的纳米复合材料的热解石墨电极（PGE）上。 -磷酸乙醇胺（DOPE），1,2-二-（9Z-十八烯酰基）-3-三甲基铵丙烷（DOTAP），1,2-二硬脂酰基-sn-甘油-3-磷酸乙醇胺-聚乙二醇（DSPE-PEG）]和也不。通过几种电化学技术对NOR直接电子转移和NO生物电催化进行了表征。生物传感器的发展还伴随着扫描电子显微镜和傅立叶变换红外光谱技术的发展。改善的酶稳定性和电子转移（1.96×10 ^-4  cm.s ^-1表观速率常数）的最佳SWCNT /（DOPE：DOTAP：DSPE-PEG）/ NOR）比为4 / 2.5 / 4（v/ v / v），它模仿了NOR环境。PGE / [SWCNTs /（DOPE：DOTAP：DSPE-PEG）/ NOR]生物传感器显示出较低的Michaelis-Menten常数（4.3μM），较宽的线性范围（0.44–9.09μM），较低的检出限（0.13μM），较高的重复性（4.1％RSD），重现性（7.0％RSD）和稳定性（约5周）。对L-精氨酸，抗坏血酸，硝酸钠，亚硝酸钠和葡萄糖的选择性测试表明，这些化合物不会显着干扰NO的生物传感（91.0±9.3％–98.4±5.3％回收率）。通过结合磷脂双层的仿生特性与SWCNT的固有特性以及NOR生物电催化活性和选择性，所提出的生物传感器是一种很有希望的NO手段。