Phase analysis light scattering PALS

LDE is limited by the experimental difficulty of distinguishing between collective and diffusive motion of colloidal particles 1137]. Phase analysis light scattering (PALS) was invented to overcome this difficulty. Instead of correlat-... 

Manerwatson, F., Tschamuter, W., and Miller, J., A new instrument for the measurement of very small electrophoretic mobilities using phase analysis light scattering (PALS), Colloids Surf. A, 140, 53, 1988. 

Phase analysis light scattering (PALS) is a technique that is very similar to laser Doppler electrophoresis (LDE) and is used to measure the electrophoretic mobilities of colloidal particles. This technique is particularly suited to measurements of charged particles suspended in nonpolar media and sensitivity of the method is far superior to that which could be obtained by LDE measurements. It makes use of a cross-beam technique and offsets one of the laser beams relative to the other by several kEIz. ... 

The present chapter is dedicated to how the zeta potential of microparticles is characterized. It is divided into five sections as follows Section 6.2 defines and describes zeta potential and introduces the most popular way to measure zeta potential, i.e., the electrophoretic mobility measurement. Section 6.3 describes the modem technology used to measure electrophoretic mobility -electrophoretic light scattering (ELS), including the optics and the sample cell followed by the data analysis of ELS experiment in Section 6.4. Section 6.5 introduces a new technique in ELS, known as phase analysis light scattering (PALS) that can be used to measure extremely small mobilities in non-polar media. 

As opposed to frequency analysis, phase analysis light scattering (PALS) analyzes particle s mobility from the phase variation of scattered light as first proposed in 1990 [64,65],... 

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