Fabrication of a GUMBOS-based acid–base indicator: smart probe for sensing acids and bases in any solvent

Abstract

This report embodies the synthesis of an ionic liquid-based pH-responsive indicator to sense acids or bases in non-polar as well as polar solvents. Herein, we have assembled a new ionic...

Ionic Liquids based Acid‐base Indicators for Aqueous to the Non‐Aqueous Medium: An Overview

“…From this observation, it can be concluded that these ILs modified indicators could be used to visualize the acid-base equilibria and determine pK a values from aqueous to non-aqueous mediums. Keeping all of these essential factors in mind, Halder and co-workers [46] have designed and developed an IL-based acidresponsive indicator to sense acids or bases to any solvents from polar to non-polar ones. They have accumulated a smart IL-based acid-responsive GUMBOS by attaching quaternary phosphonium cation, trihexyltetradecylphosphonium chloride [TTP] + with a familiar acid-base indicator, MO, which is prepared through a simple ion-exchange reaction process.…”

“…Recently, Pramanik et al [46] have also fabricated a pHresponsive MOIL NPs that compromises pH-responsive MOIL, which is disused earlier in the IL-based acid-base indicator section. The variation in the cation of the traditional MO dye by TTP + produces MOTTP that are highly hydrophobic.…”

“…[27,[36][37][38][39][40][41][42][43][44][45][46] Since the acid-base equilibrium process occurs in aqueous solutions and non-polar to polar organic solvents, several traditional organic dyes having capability as a chromogenic indicator in aqueous solutions have been modified so far within the building blocks of ILs for the visualization of acid-base equilibrium process in non-aqueous solvents. [45][46][47] Potentially, these IL-integrated acid-base sensors may have versatile applications that avoid using volatile solvents and allow strong interactions with analytes because of their high concentrations, thus increasing practical applications. Such an IL-integrated indicator would also have the potentiality for rapid quantitative detection of non-polar acids/bases and determining the pK a values in a non-aqueous medium.…”

“…Such an IL-integrated indicator would also have the potentiality for rapid quantitative detection of non-polar acids/bases and determining the pK a values in a non-aqueous medium. [46,48] Some of them are also applicable both in aqueous to non-aqueous solutions. [47,49] Although many excellent literature works are available dealing with optical and electrochemical ILs assimilated sensors, [50][51][52] comprehensive and detailed discussions on ILs integrated acid-base sensing materials for visualization acidbase equilibria and their potentiality for determination pK a values in the non-aqueous medium are very elusive to date.…”

“…Due to their significant properties and fine tunablity, GUMBOS have become potential candidates in versatile fields like extraction, separation, sensors, biocatalysis, and electrochemistry, fabrication of active pharmaceutical ingredient loaded drug carriers, microemulsion, and energy conversion field in the last decades. [27,[36][37][38][39][40][41][42][43][44][45][46] Since the acid-base equilibrium process occurs in aqueous solutions and non-polar to polar organic solvents, several traditional organic dyes having capability as a chromogenic indicator in aqueous solutions have been modified so far within the building blocks of ILs for the visualization of acid-base equilibrium process in non-aqueous solvents. [45][46][47] Potentially, these IL-integrated acid-base sensors may have versatile applications that avoid using volatile solvents and allow strong interactions with analytes because of their high concentrations, thus increasing practical applications.…”