Peptide Assembled in a Nano-confined Space as a Molecular Rectifier for the Availability of Ionic Current Modulation

Abstract

Bioinspired nanochannels have emerged as a powerful tool for bioengineering and biomedical research due to their robust mechanical and controllable chemical properties. Inspired by inward-rectifier potassium (K+) channels, herein, the charged peptide assembly has been introduced into a nano-confined space for the modulation of ion current rectification (ICR). Peptide-responsive reaction-triggered sequence changes can contribute to polarity conversion of the surface charge; therefore, ICR reversal (ICRR) is generated. Compared with other responsive elements, natural charged peptides show the merit of controllable charge polarity. By electrochemically monitoring the ICRR as an output signal, one can utilize the peptide assembly-mediated ICRR to construct an ionic sensory platform. In addition, a logic gate has been established to demonstrate the availability of an ionic sensory platform for inhibitor screening. As peptide nanoassemblies may also have various structures and functions due to their diverse properties, the ionic modulation system can provide alternatives for the assay of peptide-associated biotargets with biomedical applications.

Application of functional peptides in the electrochemical and optical biosensing of cancer biomarkers

“…Electrochemical analysis of MMP-2 was also realized by immobilizing the peptide substrate at varied biosensing interfaces. 34,57,58 In one such work, our group constructed an electrochemical platform for the assay of MMP-2 by self-assembling peptide substrates in the nanochannels. 57 As shown in Fig.…”

“…34,57,58 In one such work, our group constructed an electrochemical platform for the assay of MMP-2 by self-assembling peptide substrates in the nanochannels. 57 As shown in Fig. 2C, a porous anodic alumina film with asymmetrical nanochannels was decorated with peptide substrates that contained an MMP-2specific substrate sequence (PLGVR) and several positively or negatively charged residues (DD and KKK).…”

Nanoporous anodic alumina-based iontronics: fundamentals and applications

“…The proposed peptide-modified NAA displayed good selectivity towards MMP-2 despite the presence of other enzymes and proteins. 187 Zhao et al fabricated a dual-stimuli responsive NAA membrane for controllable drug release. The top layer of the NAA membrane was modified with a colipid layer consisting of a natural phospholipid and a thermoresponsive polymer, whereas drug was loaded at the bottom layer of NAA.…”

Surfactant-Assisted Assembly of Dipeptide Forming a Broom-like Structure

“…Multiple strategies have been successfully used for the assembly of peptides, such as solvent-induced, sonication-assisted, ionic, vaporization-induced, coordination-assisted, and surfactant-assisted assembly, as well as organic or water gelation, etc. [ 26 , 27 , 28 , 29 , 30 , 31 , 32 ]. Surfactants change the solvent environment and modulate interactions with peptides due to their hydrophilic head group and hydrophobic tail groups.…”