pH at the micellar interface: Synthesis of pH probes derived from salicylic acid, acid–base dissociation in sodium dodecyl sulfate micelles, and Poisson–Boltzmann simulation

Outcomes after the use of gastrostomy tubes in patients whose head and neck cancer was managed with radiation therapy

“…The relationships between p K a , p K app and thermodynamic values of the dissociation constants of weak acids have been described 28, 37. It is adequate, however, to stress that the relevant sites where reactions take place at the micellar interface are complex and in fact the estimates for ionic strength in typical reaction region at the micellar interface vary from 0.8 to 2.2 M 37, 40, 41. There are questions about the significance of ion strength concepts in such a reduced dimensionality 47.…”

Effects of Micelles and Vesicles on the Oximolysis of p‐Nitrophenyl Diphenyl Phosphate: A Model System for Surfactant‐Based Skin‐Defensive Formulations against Organophosphates

“…The p K a 's of I and V were 11.68 and 8.35 respectively. Oximes II , III , and IV aggregate in water and the p K a 's of the nonaggregated form could not be determined with the methods used here 40. The values of p K a for II and III were taken to be the same of that of I .…”

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

“…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):…”

“…On the other hand, it has been suggested that the acidity constant is an intrinsic property of a compound and is independent of the presence of micelles, as long as the environment is sufficiently hydrated. Hence, the acidity constants in water and in aqueous solution were set equal for further calculations in previous studies (Saikia et al, 2005;Souza et al, 2006). The dielectric constant of the headgroup region of non-ionic emulsifiers has been determined to be around 30-35 (Fernandez & Fromherz, 1977).…”

“…The difference in the polarity between buffer solution and the outer Stern layer, where hydroxycinnamic acids are solubilised, therefore does not contribute to the pK app a value in the SDS micelle. Thus, pK a;w was used for calculating the pH value at the solubilisation site (pH loc ) according to Souza et al (2006). In addition, it is possible to calculate the surface pH according to the PIE model.…”