Improvement of Stability and Transdermal Delivery of Bioactive Compounds in Green Robusta Coffee Beans Extract Loaded Nanostructured Lipid Carriers

Table 6

Mean particle size, polydispersity index (PDI), and zeta potential of NLCs with different ultrasonication time and surfactant concentrations.

Placebo-NLCs	Ultrasonication time (min)	Surfactant (% w/w)	Particle size (nm)	PDI	Zeta potential (mV)
A1	5	5	219.5 ± 0.5^a	0.3 ± 0.02^a	−21.7 ± 0.5^a
A2	15	5	150.7 ± 1.5^b	0.3 ± 0.04^a	−20.7 ± 0.2^a
B1	5	7.5	194.9 ± 2.6^c	0.2 ± 0.02^b	−30.5 ± 0.4^b
B2	15	7.5	152.4 ± 0.9^b	0.2 ± 0.01^b	−28.9 ± 0.8^b

Different letters within the same column mean significant difference ().