Single Fusion Events at Polarized Liquid-Liquid Interfaces.

A new electrochemical framework for tracking individual soft particles in solution and monitoring their fusion with polarized liquid-liquid interfaces is reported. The physicochemical principle lies in the interfacial transfer of an ionic probe confined in the particles dispersed in solution and that is released upon their collision and fusion with the fluid interface. As a proof-of-concept, spike-like transients of a stochastic nature are reported in the current-time response of 1,2-dichloroethane(DCE)|water(W) submilli-interfaces after injection of DCE-in-W emulsions.

Some insights into the facilitated ion transfer voltammetric responses at ITIES exhibiting interfacial and bulk membrane kinetic effects.

General analytical equations corresponding to the Facilitated Ion Transfer (FIT) at ITIES (Interface between Two Immiscible Electrolyte Solutions) are presented for the most frequent case in which the complexing agent is present only in the organic phase, and considering both the ion transfer and the chemical complexation kinetic effects. Under these conditions, the FIT process can be regarded as an EC mechanism. This study is of great interest to elucidate the origin of the kinetic effects which affect the electrochemical signal.

Lability of metal complexes at spherical sensors. Dynamic voltammetric measurements.

The diffusive-kinetic steady-state (dkss) approximation is applied to the case of a metal ion reaching a transforming/consuming spherical surface (sensor) when the ion is involved in a complexation reaction in solution. Simple time-dependent expressions for the surface metal flux, the lability degree and the half-wave potential are presented, valid for any value of the ratio of concentrations at the surface and the sensor radius. The solution presented is compared with other theoretical approaches, such as the kinetic steady state (kss) and the total steady state (tss), pointing out that the easy dkss approach is much more accurate than the tss one to study the metal flux and the lability degree for any value of the radius, from ultramicro to planar sensors.