Translocation Behaviors of Synthetic Polyelectrolytes through Alpha-Hemolysin (α-HL) and Mycobacterium smegmatis Porin A (MspA) Nanopores

Abstract

DNA has been used as probes for nanopore sensing of noncharged biomacromolecules due to its negative phosphate backbone. Inspired by this, we explored the potential of diblock synthetic polyelectrolytes as a more flexible and less expensive nanopore sensing probe by investigating translocation behaviors of PEO-b-PSS and PEO-b-PVBTMA through commonly used alpha-hemolysin (α-HL) and Mycobacterium smegmatis porin A (MspA) nanopores. Translocation recordings in different configurations of pore orientation and testing voltage indicated efficient PEO-b-PSS translocations through α-HL and PEO-b-PVBTMA translocations through MspA. This work provides insight into synthetic polyelectrolyte-based probes to expand probe selection and flexibility for nanopore sensing.

Classification and applications of nanomaterials in vitro diagnosis

“…Several bio-nanopores are routinely employed, including α-hemolysin (α-HL), Mycobacterium smegmatis porin A (MspA), aerolysin (AeL), and Fragaceatoxin C (FraC) [ [75] , [76] , [77] , [78] ]. α-HL nanopores were utilized to study the aggregation of Aβ associated with Alzheimer's disease (AD).…”

Patterning amyloid-β aggregation under the effect of acetylcholinesterase using a biological nanopore - an in vitro study

“…In general, an applied electric potential difference drives individual target analyte molecules to translocate through the sensing region of the nanopore, which is embedded inside a stable lipid bilayer separating the electrolytic solution into two chambers. Based on the current blockade depth (I/I 0 ), caused by the occlusion of a translocating molecule in the sensing region, and the dwell time, indicating its duration inside the nanopore, the size, charge, and other properties of the analyte can be characterized [ 24 – 27 ]. Herein, we use the widely employed α-hemolysin (α-HL) pore-forming protein to sense and characterize Aβ peptides.…”

Quantitation of Circulating Mycobacterium tuberculosis Antigens by Nanopore Biosensing in Children Evaluated for Pulmonary Tuberculosis in South Africa

“…Utilizing nanometer-scale pores in biological proteins or fabricated from artificial, solid-state membranes, nanopore sensing has shown single-molecule sensitivity and demonstrated excellent accuracy for amino acid identification and nucleic acid sequencing. − Nanopore sensing has also displayed great potential for protein analysis, and has begun to emerge as a biomarker detection tool for clinical use. − Theoretically, the concentration of an analyte can be determined by recording and statistically analyzing the frequency of ionic current blockade events induced by translocation of single analyte molecules through the nanopore under an applied electrical potential. − In practice, to obtain statistically significant numbers of translocation events within a reasonable measurement time, the concentrations of the analyte must be higher than the nanomolar level . Additionally, due to the nonselective translocation of analytes in nanopores and the stochastic nature of the electrical current blockade signals, different analytes often generate similar signals.…”