Thionine-functionalized three-dimensional carbon nanomaterial-based aptasensor for analysis of Aβ oligomers in serum

• Published in: Analytica chimica acta 2021-10, Vol.1183, p.338990-338990, Article 338990
• Main Authors: Tao, Dan, Xie, Chang, Fu, Sinan, Rong, Shuang, Song, Shizhen, Ye, Huarong, Jaffrezic-Renault, Nicole, Guo, Zhenzhong
• Format: Article
• Language: English
• Subjects: Alzheimer's disease; Analytical chemistry; Aptasensor; Aβ oligomers; Biochemistry, Molecular Biology; Chemical Sciences; Human serum; Life Sciences; Th-rGO-MWCNTs
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2021.338990

How to sensitively detect early biomarkers of Alzheimer's disease (AD) is nowadays, one of the major challenges. In this work, Aβ oligomers (AβO), one of the AD biomarkers, was analyzed using an electrochemical aptasensor, which was prepared based on thionine (Th) - functionalized three - dimensional carbon nanomaterials (reduced graphene oxide (rGO) and multi-wall carbon nanotubes (MWCNTs)) immobilized DNA-aptamer. Th, a positively charged planar aromatic molecule, form many π - π conjugated structures with rGO and MWCNTs, then improving the structural stability, electron transfer and the capacitive properties of Th-rGO-MWCNTs nanocomposites. Under the optimal conditions, differential pulse voltammetry (DPV) current responses decreased with the increase of AβO concentration. The obtained AβO aptasensor presented a wide linear range of 0.0443 pM–443.00 pM and limit of detection (LOD) was 10 fM. Meanwhile, AβO aptasensor displayed remarkable stability and selectivity. It has a great potential for early diagnosis of AD in human real serum samples. [Display omitted] •The thionine-functionalized three-dimensional carbon nanomaterial presented excellent electrical conductivity.•This aptasensor exhibited highly sensitive and stability for AβO quantification, and reached the LOD of 10 fM.•AβO aptasensor showed excellent ability for detecting 20 serum samples, and had a great potential for early diagnosis of AD.