Meghdad Kamali Moghaddam

This study is focused on the preparation of n-nonadecane-loaded calcium alginate capsules by coaxial electrospray technique. The solution and process parameters such as sodium alginate concentration, polymer feeding rate, needle gauge, needle length, needle-to-collector distance, and stirring speed were optimized through Taguchi method. These parameters were selected as variables, and three levels of them were introduced into L27 orthogonal arrays. Taguchi’s signal-to-noise ratio and analysis of variance were used to minimize the response and find the effect of control factors on it, respectively. The setup of the two-axial nozzle and feed rates of core/shell solutions were studied, as well. Optical microscopy, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy were used for characterization of the capsules. The results showed that the sodium alginate concentration and the needle gauge are important factors for capsulated alginate material. The optical microscope images and the FTIR spectra confirmed that the alginate shell successfully fabricated the n-nonadecane materials. SEM analysis showed that at the optimal conditions, micro- and nano-capsules were prepared with nearly spherical shape. The results showed that when the inner needle tip was displaced 0.5 mm ahead of the tip of the outer needle, the envelopment of the core polymer was better accomplished by the outer polymer.