Jeong, Dahye Kim, Jinsik Chae, Myung-Sic Lee, Wonseok Yang, Seung-Hoon Kim, YoungSoo Kim, Seung Min Lee, Jin San Lee, Jeong Hoon Choi, Jungkyu Yoon, Dae Sung Hwang, Kyo Seon 2024-01-19T22:33:26Z 2024-01-19T22:33:26Z 2021-09-03 2018-06 1424-8220 https://pubs.kist.re.kr/handle/201004/121321 Determination of the conformation (monomer, oligomer, or fibril) of amyloid peptide aggregates in the human brain is essential for the diagnosis and treatment of Alzheimer's disease (AD). Accordingly, systematic investigation of amyloid conformation using analytical tools is essential for precisely quantifying the relative amounts of the three conformations of amyloid peptide. Here, we developed a reduced graphene oxide (rGO) based multiplexing biosensor that could be used to monitor the relative amounts of the three conformations of various amyloid- 40 (A40) fluids. The electrical rGO biosensor was composed of a multichannel sensor array capable of individual detection of monomers, oligomers, and fibrils in a single amyloid fluid sample. From the performance test of each sensor, we showed that this method had good analytical sensitivity (1 pg/mL) and a fairly wide dynamic range (1 pg/mL to 10 ng/mL) for each conformation of A40. To verify whether the rGO biosensor could be used to evaluate the relative amounts of the three conformations, various amyloid solutions (monomeric A40, aggregated A40, and disaggregated A40 solutions) were employed. Notably, different trends in the relative amounts of the three conformations were observed in each amyloid solution, indicating that this information could serve as an important parameter in the clinical setting. Accordingly, our analytical tool could precisely detect the relative amounts of the three conformations of A40 and may have potential applications as a diagnostic system for AD. English MDPI ALZHEIMERS-DISEASE CEREBROSPINAL-FLUID BETA-PEPTIDE TAU CSF AGGREGATION FIBRILS PROTEIN BRAIN NEURODEGENERATION Multifunctionalized Reduced Graphene Oxide Biosensors for Simultaneous Monitoring of Structural Changes in Amyloid-40 Article 10.3390/s18061738 1 SENSORS, v.18, no.6 SENSORS 18 6 scie scopus 000436774300072 2-s2.0-85047861362 Chemistry, Analytical Engineering, Electrical & Electronic Instruments & Instrumentation Chemistry Engineering Instruments & Instrumentation Article ALZHEIMERS-DISEASE CEREBROSPINAL-FLUID BETA-PEPTIDE TAU CSF AGGREGATION FIBRILS PROTEIN BRAIN NEURODEGENERATION reduced graphene oxide(rGO) Alzheimer&apos s disease amyloid beta biosensor