Biomimetic stimuli‐responsive nanochannels and their applications

Abstract

Biomimetic smart nanochannels have been studied extensively to achieve the precise ionic transport compared to biological ion channels. Similar to ion channels in living organisms, biomimetic smart nanochannels can respond to various stimuli, which allows for promising applications in many fields. In this review, we mainly summarize the recent advances in the design of biomimetic stimuli‐responsive nanochannels and their potential applications including biosensors and drug delivery. Finally, an outlook on the challenges and opportunities for biomimetic stimuli‐responsive nanochannels is provided.

Bioinspired nanochannels based on polymeric membranes

“…Biological ion channels constructed by membrane proteins can get open and closed in response to external stimuli to regulate ion transport across the cell membrane [9,47], which is an important physiological activity in the metabolism of living cells. Like biological ion channels, bioinspired nanochannels also have three basic characteristics associated with wide biological roles: ion selectivity, ion gating and ionic rectification [14].…”

“…The other is to functionalize some nanochannels [14]. We can use functional molecules to achieve the control of various stimulating ion migrations in the nanochannels [9,56,60,61]. In next section, we will briefly introduce the preparation processes of polymer-based nanochannels.…”

“…Polymer-based nanochannels are the most available and functionalized substrates in solid nanochannels. Track etching technology is the most commonly used method for the preparation of polymer-based nanochannels for two main reasons: nanochannels of various shapes can be prepared by track etching [9,62], such as cylinder [63,64], dumbbell type [65], hourglass type [66][67][68], cigar type [60], cone type [69], and bullet type [26] (Fig. 3).…”

“…However, the lipid bilayer is fragile and sensitive, and it is difficult to artificially adjust working environment to biological systems. Inspired by biological nanochannels, researchers have developed artificial nanochannels functioning like the ion channel or nanopore in biological system membranes [1,6,7], called "bioinspired nanochannels" [8][9][10][11][12]. Bioinspired nanochannels have significant advantages over nanochannels embedded in lipid membranes: chemical and physical stability, flexibility in size and shape, and easy fabrication of high-density arrays [13,14].…”

Molecule‐Responsive Polymer Monolith as a Smart Gate Driven by Host–Guest Interaction with Morphology Restoration

“…Inspired by the above mechanism, researchers have developed polymer materials for controlling the liquid flow in microfluidic materials using a stimuli‐responsive hydrogel or grafted onto the liquid channel surface with stimuli‐responsive polymers. [ 1,2 ] In recent years, flow control devices that respond to the changes in heat, pH, and light have been designed [ 3–6 ] for transportation control, sensing, and medical applications. [ 7–11 ] However, reports based on controlling the permeability in response to molecules are insufficient.…”