zetapotential indicates the stability of formulation interms of the particle agglomeration capacity if liposome shows zetapotential above +/- 30 indicates the good atbility generally the zetapotential was depend up on
1. The polymer concentration
2. Medium surrounding liposomes during measurement
surface charge of vesicular systems have great advantage over stability of system as well as enhanced systemic uptake. An excess of ±25-30 zeta value was reported to play a prominent role in improving the stability of vesicular systems and more over encapsulation of charged molecules was influenced by surface charge induced by charge inducers and pH of the medium which they are formed/present. More over route of delivery demands the extent and quality of surface charge for better systemic exposure. Find the attached link which would really help in this concern i believe. All the very best.
The more surface charge resulting better emulsion stability. but in higher surface charge (more than 40) particles causes some effect on suspension medium and may result to aggregation of particles.