Use of a solid‐state nanopore for profiling the transferrin receptor protein and distinguishing between transferrin receptor and its ligand protein

Abstract

A nanopore device is capable of providing single‐molecule level information of an analyte as they translocate through the sensing aperture—a nanometer‐sized through‐hole—under the influence of an applied electric field. In this study, a silicon nitride (SixNy)‐based nanopore was used to characterize the human serum transferrin receptor protein (TfR) under various applied voltages. The presence of dimeric forms of TfR was found to decrease exponentially as the applied electric field increased. Further analysis of monomeric TfR also revealed that its unfolding behaviors were positively dependent on the applied voltage. Furthermore, a comparison between the data of monomeric TfR and its ligand protein, human serum transferrin (hSTf), showed that these two protein populations, despite their nearly identical molecular weights, could be distinguished from each other by means of a solid‐state nanopore (SSN). Lastly, the excluded volumes of TfR were experimentally determined at each voltage and were found to be within error of their theoretical values. The results herein demonstrate the successful application of an SSN for accurately classifying monomeric and dimeric molecules while the two populations coexist in a heterogeneous mixture.

Exploring single-molecule interactions: heparin and FGF-1 proteins through solid-state nanopores

“…46,47 O'Donohue et al demonstrated the successful classification of the monomeric and dimeric forms of human serum transferrin receptor proteins through SSNs and confirmed the coexistence of both forms in a heterogeneous mixture. 48 The research findings of Yin et al exemplify the use of nanopores of varying diameters in the discrimination of ferritin and apo-ferritin, which display identical exterior structures and divergent interior structures. 49 Thus, it is evident that SSNs can be productively used in discriminating protein-protein interactions.…”

In‐situ PLL‐g‐PEG Functionalized Nanopore for Enhancing Protein Characterization

“…In the other study, Matthew O′Donohue et al. were able to distinguish the transferrin protein and its receptor populations by solid‐state nanopores [25] . Also, a solid‐state nanopore was used to quantify the aggregation of different proteins based on their non‐uniform charge distribution by Mitu C. Acharjee et al [26] …”

“…[23] For instance, the translocation of more than a million-protein using modified solid-state nanopores and a method for restoring clogged pores in real-time were investigated by Jugal Saharia et al [24] In the other study, Matthew O'Donohue et al were able to distinguish the transferrin protein and its receptor populations by solid-state nanopores. [25] Also, a solid-state nanopore was used to quantify the aggregation of different proteins based on their non-uniform charge distribution by Mitu C. Acharjee et al [26] Blood components such as Alpha-1 antitrypsin (AAT) play a critical role in preventing tissue breakdown by proteolytic enzymes. It protects the lungs from neutrophil elastase, an enzyme responsible for degrading elastin.…”