Streaming potential studies of colloid, polyelectrolyte and protein deposition

Area of Science:

• Surface science
• Colloid and interface science
• Electrochemistry

Background:

• Understanding interfacial layers is crucial in fields like materials science and biotechnology.
• Electrokinetic phenomena offer sensitive probes for characterizing interfaces.
• Previous models often simplified transport and surface interactions.

Purpose of the Study:

• To review recent advancements in electrokinetic determination of interfacial monolayers.
• To present theoretical models for particle transport, deposition kinetics, and electrokinetic responses.
• To interpret experimental data for various monolayer systems using these models.

Main Methods:

• Theoretical modeling of particle transport, diffusion, and random sequential adsorption (RSA).
• Analysis of blocking effects and jamming coverage in monolayer formation.
• Electrokinetic measurements, including streaming potential and streaming current.
• Interpretation of experimental data using generalized RSA and electrokinetic models.

Main Results:

• Analytical formulae for limiting flux and diffusion coefficients of particles.
• Characterization of blocking effects using the random sequential adsorption model.
• Quantitative analysis of monolayer kinetics and structure, considering transport coupling.
• Dependence of jamming coverage on ionic strength.
• Quantitative evaluation of streaming current and potential based on surface coverage and zeta potential.
• Validation of electrokinetic measurements for in situ monolayer analysis.

Conclusions:

• Electrokinetic methods provide precise, in situ determination of particle, protein, and polyelectrolyte monolayers.
• Theoretical models, especially generalized RSA, effectively explain experimental observations.
• Interfacial monolayer properties are sensitive to ionic strength and surface characteristics.