Abstract Development of a facile method for the detection of nitrite ion is very important due to its huge impact on environment. In the present study, water soluble bovine serum albumin capped gold nanoparticles (BSA-AuNPs) were directly attached on glassy carbon (GC) electrode for the sensitive determination of nitrite ion. The BSA-AuNPs were synthesized and HR-TEM images showed that the average size was ~5 nm. The BSA-AuNPs were then directly attached on GC electrode without any external linker and confirmed by SEM, EDS, XPS, DRS and CV. The appearance of peak at 286 eV (C-N) in XPS confirmed that BSA-AuNPs were attached on GC substrate through Michaeli's nucleophilic addition. The GC/BSA-AuNPs electrode showed an excellent catalytic activity towards nitrite by not only shifting its oxidation potential towards less positive potential by 150 mV but also enhanced its oxidation current by 3-fold compared to bare GC electrode. The amperometric current was increased linearly while increasing nitrite concentration from 10 × 10−9 to 1 × 10−6 M (R2 = 0.9917) and the limit of detection (LOD) by amperometry was found to be 2 × 10−9 M (S/N = 3). The real-time application of the present electro-catalyst was evidenced by determining nitrite in water samples.

中文翻译：

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白蛋白包覆金纳米粒子的合成及其直接附着在玻碳电极上测定亚硝酸根离子

摘要 由于亚硝酸根离子对环境的巨大影响，开发一种简便的亚硝酸根离子检测方法非常重要。在本研究中，水溶性牛血清白蛋白包覆的金纳米粒子 (BSA-AuNPs) 直接附着在玻璃碳 (GC) 电极上，用于灵敏测定亚硝酸根离子。合成了 BSA-AuNPs，HR-TEM 图像显示平均尺寸为 ~5 nm。然后将 BSA-AuNPs 直接连接到 GC 电极上，无需任何外部连接器，并通过 SEM、EDS、XPS、DRS 和 CV 进行确认。XPS 中 286 eV (CN) 峰的出现证实了 BSA-AuNPs 通过 Michaeli 的亲核加成附着在 GC 底物上。GC/BSA-AuNPs 电极对亚硝酸盐显示出优异的催化活性，与裸 GC 电极相比，不仅将其氧化电位向较低的正电位移动 150 mV，而且将其氧化电流提高了 3 倍。当亚硝酸盐浓度从 10 × 10−9 增加到 1 × 10−6 M (R2 = 0.9917) 时，安培电流线性增加，电流法检测限 (LOD) 为 2 × 10−9 M (S /N = 3）。通过测定水样中的亚硝酸盐证明了本电催化剂的实时应用。9917），电流分析法的检测限 (LOD) 为 2 × 10−9 M (S/N = 3)。通过测定水样中的亚硝酸盐证明了本电催化剂的实时应用。9917），电流分析法的检测限 (LOD) 为 2 × 10−9 M (S/N = 3)。通过测定水样中的亚硝酸盐证明了本电催化剂的实时应用。