Chemically induced fluorescence switching of carbon-dots and its multiple logic gate implementation.

Namasivayam Dhenadhayalan,King-Chuen Lin

doi:10.1038/srep10012

Namasivayam Dhenadhayalan, King-Chuen Lin

Open Access

https://doi.org/10.1038/srep10012

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Abstract

Investigations were carried out on the carbon-dots (C-dots) based fluorescent off - on (Fe3 + - S2O32−) and on - off (Zn2 + - PO43−) sensors for the detection of metal ions and anions. The sensor system exhibits excellent selectivity and sensitivity towards the detection of biologically important Fe3 + , Zn2 + metal ions and S2O32−, PO43− anions. It was found that the functional group on the C-dots surface plays crucial role in metal ions and anions detection. Inspired by the sensing results, we demonstrate C-dots based molecular logic gates operation using metal ions and anions as the chemical input. Herein, YES, NOT, OR, XOR and IMPLICATION (IMP) logic gates were constructed based on the selection of metal ions and anions as inputs. This carbon-dots sensor can be utilized as various logic gates at the molecular level and it will show better applicability for the next generation of molecular logic gates. Their promising properties of C-dots may open up a new paradigm for establishing the chemical logic gates via fluorescent chemosensors.

Highlights

Chemical based molecular logic gates received extensive attention due to its fascinating significance for the development of molecular-scale electronic devices, which perform Boolean logic operations in response to chemical inputs
The performance of various logic gate functions depend on the association and dissociation of metal ions (Fe3 + or Zn2 + ) and anions (S2O32− or PO43−) with C-dots and their corresponding fluorescence intensity emitted by C-dots
These results show that the use of low or high concentration of PO43− as input 2 along with Zn2 + as input 1 generated OR or XOR logic gate functions[42,43] respectively (Fig. 8), revealing that the different logic operation can be achieved by varying the concentration of inputs

Summary

Introduction

Chemical based molecular logic gates received extensive attention due to its fascinating significance for the development of molecular-scale electronic devices, which perform Boolean logic operations in response to chemical inputs. Based on the sensing results we implemented the molecular logic gates behavior by observing the fluorescence response, i.e., change in the fluorescence intensity with varying the chemical inputs such as metal ions and anions. These results proved that this off-on and on-off fluorescence process depend on the functional groups present on the C-dots surface and affinity nature of metal ion with anions.

Results

Conclusion