Table 4. Sen's slope analysis data for correlation between speed (rpm) and core size (nm), hydrodynamic diameter (nm), zeta-potential (mV) and polydispersity index (PDI).

Parameter	Core size (nm)	Hydrodynamic diameter (nm)	Zeta potential (mV)	Polydispersity index (PDI)
Sen's slope	−0.075	−0.298	−0.067	0.001
Lower bound (95%)	−0.170	−0.545	−0.131	−0.003
Upper bound (95%)	−0.022	0.200	0.024	0.000