Abstract Enhancing catalytic property as well as realizing direct electron transfer between the nanomaterials and the electrode surface is key to fabricating the catalytic materials. In the present research, a facile method is reported to design silver-grafted silica nanohybrids (SiO2@Ag-NHs) via sonolysis of a solution comprising of silver nitrate (AgNO3) and aminosilane functionalized silica nanospheres (SiO2 NSs) in the presence of sodium borohydride (NaBH4). The formation of SiO2@Ag-NHs was characterized using UV-visible spectroscopy, XRD, HRTEM, XPS analysis and its electrochemical sensing behaviours were examined for Tryptophan (Trp); an important biomarker of gastric cancer. The modified sensor (SiO2@Ag-NHs/GCE) shows enhanced electrocatalytic performance for Trp with a considerable detection limit (LoD) of 0.127 µM (S/N=3), quantification limit (LoQ) of 0.193 µM (S/N=10), and a sensitivity as high as 1.77 µA µM−1 cm−2. Finally, the practicability of the proposed SiO2@Ag-NHs/GCE was evaluated for quantification of Trp in pharmaceutical formulation and human serum samples and exhibited satisfactory recovery results.

中文翻译：

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通过氨基硅烷启发的表面功能化制备银接枝二氧化硅纳米杂化物以增强对胃癌生物标志物的电化学性能

摘要 提高催化性能以及实现纳米材料与电极表面之间的直接电子转移是制备催化材料的关键。在本研究中，报道了一种简便的方法来设计银接枝的二氧化硅纳米杂化物（SiO2@Ag-NHs），通过在钠的存在下对硝酸银（AgNO3）和氨基硅烷官能化二氧化硅纳米球（SiO2NSs）组成的溶液进行声分解硼氢化物 (NaBH4)。使用紫外-可见光谱、XRD、HRTEM、XPS 分析表征 SiO2@Ag-NHs 的形成，并检查其对色氨酸 (Trp) 的电化学传感行为；胃癌的重要生物标志物。改进的传感器 (SiO2@Ag-NHs/GCE) 显示出增强的 Trp 电催化性能，检测限 (LoD) 为 0.127 µM (S/N=3)，定量限 (LoQ) 为 0.193 µM (S/N=10)，灵敏度高达 1.77 µA µM-1 cm-2。最后，对所提出的 SiO2@Ag-NHs/GCE 的实用性进行了评估，用于定量药物制剂和人血清样品中的 Trp，并显示出令人满意的回收率。