pH‐Controlled Transition from Disaggregation to Reaggregation of Bis‐indolyl(phenyl)methane−β‐CD Conjugate Appended with Multi‐logic Operations

Abstract

Multifunctional molecular logic system is designed based on the pH responsive emission properties of Bis‐indolyl(phenyl)methane (BIPM)–β‐CD conjugates in aqueous medium. In our previous studies, BIPM molecules in water were found to form large molecular self‐aggregates that disaggregated in presence of β‐CD molecules through inclusion complexation. In the present study, transition from the disaggregated to reaggregated form of Bis‐indolyl(phenyl)methane–β‐CD conjugate was followed through alteration of the local pH from 7 to 13.2. The BIPM molecules are expected to reaggregate at high alkaline medium due to the expulsion of probes from the nano‐cages of β‐CD. The pH dependent emission spectroscopic changes are harvested to design a multi‐functional molecular logic system. The molecular system can mimic the functions of several fundamental logic gates and an ‘erase‐read‐write‐read’ memory unit. A macro‐molecular security system based on three chemical inputs is also presented here that can authenticate all‐active‐all‐possible (33) three‐character passwords with the respective unique fluorescence trajectories. Designing of molecular logic system based on the pH responsive emission properties of the aggregated and disaggregated forms of an organic probe is rather uncommon and the multifunctional logic, memory and security applications of the present system will carry significant importance in the molecular logic research.

Designing Unconventional Molecular Ternary INHIBIT Logic Gate and Crafting Multifunctional Molecular Logic Systems

“…If the absorption/FL value exceeds the set threshold, it will be considered binary 1, and if it falls below, it will be considered binary 0. Following these orthodox molecular logic gate designing approach, ,,,− we have proposed herein a range of optically adaptive molecular NOR, AND, IMPLICATION, INHIBIT, TRANSFER, COMPLEMENT, etc. The most exciting element of the current study is how a single photochemical system can be simply modified to achieve incredibly precise binary logic features (such as NOR, INHIBIT, TRANSFER, etc.)…”

“…With contemporary and parametric advances in molecular logic and smart systems designing, optical–chemical or opto-chemical molecular devices with basic structures are of interest due to the ease of design, superior selectivity, integrity, and rapid response for signal processing. − Several molecular logic systems that can execute fundamental logic operations (YES, NOT, PASS 0, PASS 1, AND, OR, NAND, NOR, XOR, XNOR, INHIBIT, IMPLICATION, etc.) have been reported previously. − The development of integrated combinational logic circuits − (adder, subtractor, multiplexer, demultiplexer, encoder, decoder, etc.)…”