Acid–base equilibrium of anionic dyes partially bound to micelles of nonionic surfactants

Impact of emulsifier microenvironments on acid–base equilibrium and activity of antioxidants

“…2) (Saikia, Bora, & Dutta, 2005;Schreier et al, 1984). It involves the dissociation of the antioxidant and the partitioning of the protonated and dissociated species between the aqueous phase and micelles.…”

“…The pH value at the solubilisation site (pH loc ) in SDS micelles was calculated according to the procedures previously described by Saikia et al (2005) and Souza et al (2006):…”

“…Depending on the emulsifier, two effects may contribute to the influence of the micellar environment: solvation or polarity effects and the local pH (Losada Barreiro, Sánchez-Paz, Pastoriza Gallego, & Brávo-Díaz, 2008). In addition, there is a difference in the partitioning between ionised and non-ionised species, i.e., the non-dissociated forms of FA and iFA are subject to stronger hydrophobic attraction by micelles, which results in a higher incorporation (Saikia et al, 2005). On the other hand, electrostatic interactions may reduce the binding to anionic micelles and increase the binding to cationic micelles.…”

Mechanically Induced Generation of Counterions Inside Surface‐Grafted Charged Macromolecular Films: Towards Enhanced Mechanotransduction in Artificial Systems

“…[17] This dye changes its color at around pH 7, from a yellow (neutral form) to a blue (anionic form) state, which can be easily detected by UV/Vis spectroscopy. [18,19] Mechanical compression was accomplished by sandwiching the brush-coated glass slides between two slabs of crosslinked poly(dimethylsiloxane) (PDMS) and placing the assembly in a holder commonly used for IR experiments on liquids. Great care was taken to ensure that the brush-coated glass slides were never dried, since dehydration would inevitably lead to (irreversible) collapse of the brushes.…”

Challenges of HPLC method development and validation for the assay of combined drug products

“…Micelle formation can be influenced by change of pH [105]. The API recovery was therefore studied in analytical samples containing increasing sodium hydroxide concentration.…”