Thyashan, Navod Ghimire, Madhav L. Lee, Sangyoup Kim, Min Jun 2024-04-11T04:30:48Z 2024-04-11T04:30:48Z 2024-04-11 2024-05 2040-3364 https://pubs.kist.re.kr/handle/201004/149635 Detection and characterization of protein-protein interactions are essential for many cellular processes, such as cell growth, tissue repair, drug delivery, and other physiological functions. In our research, we have utilized emerging solid-state nanopore sensing technology, which is highly sensitive to better understand heparin and fibroblast growth factor 1 (FGF-1) protein interactions at a single-molecule level without any modifications. Understanding the structure and behavior of heparin-FGF-1 complexes at the single-molecule level is very important. An abnormality in their formation can lead to life-threatening conditions like tumor growth, fibrosis, and neurological disorders. Using a controlled dielectric breakdown pore fabrication approach, we have characterized individual heparin and FGF-1 (one of the 22 known FGFs in humans) proteins through the fabrication of 17 +/- 1 nm nanopores. Compared to heparin, the positively charged heparin-binding domains of some FGF-1 proteins translocationally react with the pore walls, giving rise to a distinguishable second peak with higher current blockade. Additionally, we have confirmed that the dynamic FGF-1 is stabilized upon binding with heparin-FGF-1 at the single-molecule level. The larger current blockades from the complexes relative to individual heparin and the FGF-1 recorded during the translocation ensure the binding of heparin-FGF-1 proteins, forming binding complexes with higher excluded volumes. Taken together, we demonstrate that solid-state nanopores can be employed to investigate the properties of individual proteins and their complex interactions, potentially paving the way for innovative medical therapies and advancements. We present a successful discrimination of heparin, FGF-1, and heparin-FGF-1 complexes at a single-molecule level through solid-state nanopores. English Royal Society of Chemistry Exploring single-molecule interactions: heparin and FGF-1 proteins through solid-state nanopores Article 10.1039/d4nr00274a 1 Nanoscale, v.16, no.17, pp.8352 - 8360 Nanoscale 16 17 8352 8360 N scie scopus 001195043400001 Chemistry, Multidisciplinary Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Chemistry Science & Technology - Other Topics Materials Science Physics Article BINDING SPECIFICITY FAMILY FIBROBLAST-GROWTH-FACTOR SITE-DIRECTED MUTAGENESIS FACTOR-I WEIGHT HEPARIN