MP-PALS
Electrophoretic Light Scattering (ELS) is used widely for characterizing electrophoretic mobility, zeta potential or charge of nanoparticles. Wyatt Technology's breakthrough Massively Parallel Phase Analysis Light Scattering (MP-PALS) extends robust ELS measurements to proteins and other biomolecules in native buffer solutions.
MP-PALS does everything conventional zeta potential instruments can do and much more:
- Optimize stability of colloidal suspensions or biomolecular formulations
- Evaluate degradation due to accelerated stress of proteins
- Understand the different factors contributing to intermolecular forces
- Analyze compositional variants of biopolymers

Protein electrophoretic mobility as a function of formulation pH.

MP-PALS utilizes low voltage and multiple low-noise, high-dynamic range detectors in parallel to achieve the highest sensitivity without damaging fragile samples.
Application notes
Automated Electrophoretic Mobility Measurement of High Salt Solutions
Automated Measurements of Electrophoretic Mobility
Computation of Protein Net Charge from Electrophoretic Mobility
Discriminating Heparin from Chondroitin Sulfate by Charge:Mass Ratio
Charge and Interaction Analysis for Predicting Antibody Formulation Stability
Selected references
Qu, H.; Tong, S.; Song, K.; Ma, H.; Bao, G.; Pincus, S.; Zhou, W.; O'Connor, C. Controllable in situ synthesis of magnetite coated silica-core water-dispersible hybrid nanomaterials. Langmuir 2013, 29, 10573-10578.
Roberts, D.; Keeling, R.; Tracka, M.; van der Walle, C. F.; Uddin, S.; Warwicker, J.; Curtis, R. The role of electrostatics in protein-protein interactions of a monoclonal antibody. Mol. Pharm. 2014, 11, 2475-2489.
Saito, S.; Hasegawa, J.; Kobayashi, N.; Tomitsuka, T.; Uchiyama, S.; Fukui, K. Effects of ionic strength and sugars on the aggregation propensity of monoclonal antibodies: influence of colloidal and conformational stabilities. Pharm. Res. 2013, 30, 1263-1280.
Instrumentation for MP-PALS
MP-PALS Detector
Mobius™ - Massively Parallel Phase Analysis Light Scattering makes the Mobius the most sensitive electrophoretic light scattering detector available. Determines electrophoretic mobility, surface charge and zeta potential of fragile biomolecules as well as more robust nanoparticles, in native buffer. The Mobius is the only mobility detector to provide connectivity to an autosampler for hands off, multi-sample operation.
The Mobius is also the only mobility detector that measures dynamic light scattering (DLS) simultaneously with electrophoretic mobility, in the same scattering volume, to monitor potential sample degradation.
Software
DYNAMICS® - Software for MP-PALS and DLS measurements in the Mobius. Calculates electrophoretic mobility, size and size distributions, and derives zeta potential, Debye-Hückel-Henry and effective net charge.
Interested in other techniques or combining other techniques with MP-PALS?
SEC-MALS: Standard in protein, biopolymer and synthetic polymer characterizations labs around the world, Wyatt MALS detectors are valued for reliable and robust measurements.
FFF-MALS: Coupling an FFF system to a set of Wyatt MALS and/or DLS detectors creates a powerful system for accurate and robust characterization of molar mass and size distributions for simple or complex samples.
CG-MALS: Apply CG-MALS to characterize self- and hetero-association, binding affinity from pM to mM, absolute molecular stoichiometry (not just mole ratios) and more.
DLS: Measure the translational diffusion coefficients Dt of nanoparticles and colloids in solution by quantifying dynamic fluctuations in scattered light. DLS is suitable for ensemble measurements ranging from Rh values of 0.2 nm up to 5,000 nm.
SEC-IV: SEC-IV may be the optimal means of characterizing materials not amenable to SEC-MALS analysis. By simply adding a DAWN, transform a basic SEC-IV setup into a powerful SEC-MALS-IV polymer characterization station, to analyze absolute determination of molar mass and size regardless of conformation, branched polymers, copolymers and measure Mark-Houwink coefficients ab initio.