2.4.2. Confocal Laser Scanning Microscopy (CLSM)

CLSM images of the emulsions were taken with a Nikon Eclipse Ti inverted microscope (Nikon, Japan). A portion (5 mL) of the inks was stained with the appropriate amount of Nile Blue A (1.0%, w/v) in deionized water or the blend of Nile Blue A (1%, w/v) and Nile Red (0.1%, w/v) in 1,2-propanediol (including deionized water, 20 μL g^–1) to mark the protein and/or modified MMC and oil droplet, respectively. The level of both Nile blue A and Nile red solutions was 0.01% (w/v). The excitation wavelengths of the fluorescent in the system were 488 nm (Nile red) and 633 nm (Nile blue A). The ink microstructures were imaged at ambient temperature directly after staining. All images were obtained at 40× magnification and processed using Olympus Fluoview software (version 2.1, Olympus, Tokyo, Japan).⁶⁵