A label-free biosensor based on graphene and reduced graphene oxide dual-layer for electrochemical determination of beta-amyloid biomarkers
A label-free biosensor based on graphene and reduced graphene oxide dual-layer for electrochemical determination of beta-amyloid biomarkers
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DOI：
10.1007/s00604-020-04267-x
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发表时间：
2020-04-25
影响因子：
5.7
通讯作者：
Pan, Genhua
中科院分区：
文献类型：
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作者：
Sethi, Jagriti;Van Bulck, Michiel;Pan, Genhua
研制了一种用于检测阿尔茨海默病(AD)患者血浆中Aβ(1-42)生物标志物的无标记生物传感器。该平台是基于高导电性的双层石墨烯和电化学还原的氧化石墨烯(RGO)。为便于H31L21抗体的固定化，采用N-羟基丁二酰亚胺(PYR-NHS)对H31L21抗体进行双层修饰。用形态、光谱和电化学技术研究了这些修饰的效果。利用差示脉冲伏安法(DPV)对该生物传感器的响应进行了评价。数据是在类似于180mV的工作电压和50 mV的扫描速率下获得的，S(-1)。在11~55 nm的线性范围内，检测下限为2.398 pm。该生物传感器对Aβ(1-40)和ApoE epsilon 4干扰物种具有良好的特异性。因此，它为电化学测定Aβ(1-42)提供了一种可行的工具。使用添加了添加剂的人和小鼠血浆，在生物流体样品中成功地验证了该传感平台。从小鼠血浆分析得到的结果与从脑分析获得的免疫组织化学(IHC)和磁共振成像(MRI)数据一致。所提出的用于Aβ(1-42)测定的电化学系统的示意图：(A)用单层氧化石墨烯(GO)修饰石墨烯丝网印刷电极(SPE)，然后其电化学还原生成石墨烯/还原的氧化石墨烯(RGO)双层(B)，用连接物(C)修饰双层(C)，用Aβ(1-42)抗体(H31L21)(D)修饰，牛血清白蛋白(BSA)(E)和Aβ(1-42)肽(F)。
A label-free biosensor is developed for the determination of plasma-based A beta(1-42) biomarker in Alzheimer's disease (AD). The platform is based on highly conductive dual-layer of graphene and electrochemically reduced graphene oxide (rGO). The modification of dual-layer with 1-pyrenebutyric acid N-hydroxysuccinimide ester (Pyr-NHS) is achieved to facilitate immobilization of H31L21 antibody. The effect of these modifications were studied with morphological, spectral and electrochemical techniques. The response of the biosensor was evaluated using differential pulse voltammetry (DPV). The data was acquired at a working potential of similar to 180 mV and a scan rate of 50 mV s(-1). A low limit of detection (LOD) of 2.398 pM is achieved over a wide linear range from 11 pM to 55 nM. The biosensor exhibits excellent specificity over A beta(1-40) and ApoE epsilon 4 interfering species. Thus, it provides a viable tool for electrochemical determination of A beta(1-42). Spiked human and mice plasmas were used for the successful validation of the sensing platform in bio-fluidic samples. The results obtained from mice plasma analysis concurred with the immunohistochemistry (IHC) and magnetic resonance imaging (MRI) data obtained from brain analysis.Schematic representation of the electrochemical system proposed for A beta(1-42) determination: (a) modification of graphene screen-printed electrode (SPE) with monolayer graphene oxide (GO) followed by its electrochemical reduction generating graphene/reduced graphene oxide (rGO) dual-layer (b), modification of dual-layer with linker (c), A beta(1-42) antibody (H31L21) (d), bovine serum albumin (BSA) (e) and A beta(1-42) peptide (f).