Pore-forming toxins as tools for polymer analytics: From sizing to sequencing.

Area of Science:

• Biophysics
• Analytical Chemistry
• Materials Science

Background:

• Nanopore resistive pulse sensing (Np-RPS) is an electrical, label-free technique for single-molecule analysis.
• Pore-forming toxins serve as biological nanopores for detecting molecular properties via transient current blockades.

Purpose of the Study:

• To review the history and principles of Np-RPS.
• To explore how molecule/nanopore interactions influence data for sequencing or sizing.
• To focus on polymer characterization using specific nanopores.

Main Methods:

• Utilized staphylococcal α-hemolysin (αHL) and aerolysin (AeL) nanopores.
• Applied Np-RPS for label-free detection and characterization of single molecules.
• Focused on the molecular sizing regime for polymers and peptides.

Main Results:

• Demonstrated Np-RPS's capability for label-free single-molecule detection.
• Characterized water-soluble polymers like poly-(ethylene glycol) (PEG), homopeptides, and heteropeptides.
• Showcased the influence of nanopore configuration on extracted molecular information.

Conclusions:

• Np-RPS is a versatile tool for single-molecule polymer analytics.
• Nanopore sizing of polymers shows promise as a novel method for peptide and protein sequencing.
• The study highlights the potential of tailoring nanopore interactions for specific analytical outcomes.