Zeta potential is an important property of microspheres and often indicates the stability of microsphere preparations. In the solution of particle dispersion system, there are the same ions on the surface. Through the adsorption and diffusion effect of electrostatic gravity, the adsorption layer formed around the particle and the adjacent diffusion layer together form the double electric layer structure of the particle. The potential difference from the surface of the adsorption layer to the point where the counter ion charge is zero is called galvanic potential, namely Zeta potential. CD Formulation has our own advanced Zeta potential analyzer, and we can provide the Zeta potential measurement services for the microspheres, helping you to know the physical and chemical properties of the products.
The Zeta potential value can reflect the physical stability of the particle. The greater the Zeta potential, the stronger the repulsion between the particles, the less possibility of flocculation or deposition, and the more stable the particle in solution. Zeta potential analysis is used as a standard characterization technique to evaluate the surface of microspheres and help further reveal the properties of microspheres. Based on the professional technology and rich experience of CD Formulation, we are able to provide you with the Zeta potential tests of microspheres, the methods of which can be seen as follows:
When an electric field is applied to an electrolyte, charged particles suspended in the electrolyte are attracted towards electrodes of opposite charge, and the viscous forces acting on the particles tend to counter this motion. When these two resistance forces are in equilibrium, the particles move at a constant velocity, which is called electrophoretic mobility.
The moving velocity of liquid per unit field strength is called electroosmotic velocity. The electroosmosis rate of liquid is directly proportional to the potential of liquid and solid phase, so electroosmosis can be used to measure potential.
3. Flow potential method
Flow potential refers to the fact that when electrolyte solution flows on a charged insulated surface, free charged particles of double electric layers on the surface will move along the direction of solution flow. The movement of these charged particles leads to the accumulation of charges downstream, and the potential difference between upstream and downstream is the flow potential.
4. Ultrasonic electroacoustic method
When a voltage is applied to both sides of the colloidal solution, the motion of the dots generates sound waves. By measuring the sound waves produced, the dynamic mobility of the particles can be calculated, and finally the Zeta potential can be calculated.
Zeta potential is not usually measured directly, but can be calculated using electrophoretic measurements, which measure particle velocity under an applied electric field, i.e. by moving particles and measuring their mobility. Thus, the calculated Zeta potential depends on the theory used in these calculations, namely the relation of particle mobility to the Zeta potential. Another way to measure the potential of large particles or surfaces is to move the liquid onto the surface of the microsphere and then measure the resulting flow potential.
If you need our testing service, or if the service you want is not on the list, please feel free to contact us.