Nanocapsules were synthesized using the droplets of an oil-in-water microemulsion as a template. Ethyl butyrate was solubilized in normal saline using Tween-80, lecithin, and n-octadecyltrimethoxysilane as surfactants. A polysiloxane/silicate shell was formed at the surface of the mixed surfactant layer by cross-linking n-octadecyltrimethoxysilane and tetramethoxysilane. The shell stabilized the oil droplets against coalescence as seen by transmission electron microscopy (TEM) of the samples immediately following the synthesis and months afterward. The diameter of nanocapsules can be controlled by using different component ratios, as measured by quasi-elastic light scattering (QELS) and TEM. The efficacy of nanocapsules to sequester hydrophobic compounds made by using different formulations was studied by UV-visible spectrometry. The results showed that nanocapsules with smaller diameters are generally more efficient in the uptake process than larger ones.