The stability of charged particles or their tendency to agglomerate are determined by the strength of electrostatic repulsive forces, which are a function of the zeta potential. The zeta potential is highly affected by the surrounding medium and also different methods of zeta potential determination show different zeta potential values. Different methods cause varying accelerations of particles by external force. Measurements of the zeta potential by different methods are difficult to compare due to varying forces acting on the electric double-layer surrounding the particle. A reliable and stable zeta potential control defining the zeta potential according to the relevant method, is essential. The zeta potential controls by Applied Microspheres provide reliable zeta potential values for both electrophoretic mobility and streaming potential methods.
Applied Microspheres’ Zeta Potential Controls consist of negatively charged polystyrene particle suspensions that are designed for reproducible zeta potential validation. A special formulation ensures that the negative charge is stronger than is the case with common polystyrene suspensions. The suspension has a negligible content of charged surfactant, resulting in the reduction of background noise. Applied Microspheres Zeta Potential Controls are supplied in single use, 3 ml or 10 ml luer lock syringes, packaged in boxes of 10 or 18 syringes. Shelf life is 18 months from date of packaging. They can be stored at room temperature.