Logic Functions with Stimuli‐Responsive Single Nanopores

Abstract

We present the concept of logic functions based on a single stimuli‐responsive nanopore and analyze its potential for electrochemical transducers and actuators. The responsive molecules at the surface of the polymeric nanopore immersed in an electrolyte solution are sensitive to thermal, chemical, electrical, and optical stimuli, which are the input signals required to externally tune the conductance of the nanopore (the logical output). A single nanostructure can be operated as a resistor or as a diode with a broad range of rectifying properties, allowing for logical information‐processing schemes that are useful pH and temperature sensors, electro‐optical detectors, and electrochemical actuators and transducers. Some of the limitations to be addressed in practical applications are also cited.

Multipore membranes with nanofluidic diodes allowing multifunctional rectification and logical responses

“…The use of different solutions in the three volumes of the cell allows the multifunctional electrical responses. 3,28 Figures 2(a)-2(c) show three control experiments conducted under different conditions. Fig.…”

“…The wide range of surface functionalizations currently available for biologically oriented sensors and actuators tuned by different chemical, thermal, electrical, and optical signals [1][2][3][4][5][6][7] is remarkable. Practical applications are, however, limited by the high variability observed in the individual nanostructure responses and the continuous operation after several cycles.…”

“…Thus, the membrane performance is entirely based on the pH-reversed ion current rectification 11 and does not require highly specific functionalizations of the pore surface. 3,12 The multifunctional response is robust enough to permit different logical functions including NOR and INHIBIT gates, which are of current interest for liquid state transducers and actuators. 3,[13][14][15][16] The NOR gate is functionally complete and the INHIBIT function is difficult to implement in practice because it should give the output "1" only for one particular combination of inputs "0" and "1."…”

“…3,12 The multifunctional response is robust enough to permit different logical functions including NOR and INHIBIT gates, which are of current interest for liquid state transducers and actuators. 3,[13][14][15][16] The NOR gate is functionally complete and the INHIBIT function is difficult to implement in practice because it should give the output "1" only for one particular combination of inputs "0" and "1." While this requirement may be fulfilled by using three rather than two inputs and particular combinations of two of the basic functions, 17 we have used here only two inputs.…”

Ionic Transport through Chemically Functionalized Hydrogen Peroxide-Sensitive Asymmetric Nanopores

“…24 Equations (1)- (3) can be integrated numerically to give the ionic flux densities, and then the total electric current I through the nanopore, at each applied voltage V (see references 22 and 26 for details). The above model is useful to describe the IV curves of different nanopores [22][23][24][25][26] using a reduced number of fitting parameters. Figure 2d-f shows that this is also the case of the present experimental results.…”