Munge Bernard S, Krause Colleen E, Malhotra Ruchika, Patel Vyomesh, Gutkind J Silvio, Rusling James F
Department of Chemistry, Salve Regina University, 100 Ochre Point Avenue, RI 02840, USA.
Electrochem commun. 2009;11(5):1009-1012. doi: 10.1016/j.elecom.2009.02.044.
Electrochemical immunosensors based on single wall nanotube (SWNT) forests and 5 nm glutathione-protected gold nanoparticles (GSH-AuNP) were developed and compared for the measurement of human cancer biomarker interleukin-6 (IL-6) in serum. Detection was based on sandwich immunoassays using multiple (14-16) horseradish peroxidase labels conjugated to a secondary antibody. Performance was optimized by effective blocking of non-specific binding (NSB) of the labels using bovine serum albumin. The GSH-AuNP immunosensor gave a detection limit (DL) of 10 pg mL(-1) IL-6 (500 amol mL(-1)) in 10 muL calf serum, which was 3-fold better than 30 pg mL(-1) found for the SWNT forest immunosensor for the same assay protocol. The GSH-AuNPs platform also gave a much larger linear dynamic range (20-4000 pg mL(-1)) than the SWNT system (40-150 pg mL(-1)), but the SWNTs had 2-fold better sensitivity in the low pg mL(-1) range.
基于单壁纳米管（SWNT）森林和5纳米谷胱甘肽保护的金纳米颗粒（GSH-AuNP）开发了电化学免疫传感器，并对其在血清中检测人类癌症生物标志物白细胞介素-6（IL-6）的性能进行了比较。检测基于夹心免疫分析，使用与二抗偶联的多个（14 - 16个）辣根过氧化物酶标记物。通过使用牛血清白蛋白有效阻断标记物的非特异性结合（NSB）来优化性能。GSH-AuNP免疫传感器在10微升小牛血清中对IL-6的检测限（DL）为10皮克/毫升（500阿托摩尔/毫升），对于相同的检测方案，这比SWNT森林免疫传感器的30皮克/毫升要好3倍。GSH-AuNP平台的线性动态范围（20 - 4000皮克/毫升）也比SWNT系统（40 - 150皮克/毫升）大得多，但在低皮克/毫升范围内，SWNT的灵敏度要好2倍。
