2.5. Encapsulation Efficiency Determination

Encapsulation efficiency (EE%) is defined as the percentage of loaded drug respect to the total amount of the used drug, and is calculated through this Equation (1),

where gi indicates the total amount of drug used and gf the loaded drug amount.

SLNs were solubilized in a water/methanol solution (1:9) and were sonicated for 15 min at 37 °C. The absorbance of the compounds was determined by UV-Vis spectrometry at wavelength for LNA (λ = 264 nm, ε = 17,596×).

The tests were carried out in triplicate and the results were in agreement with ±5% standard error.