Effect of electromagnetic field and surface modification on the electrical behavior of novel solid lipid nanoparticles covered with L-arginine

Solid lipid nanoparticles (SLNs) were fabricated with modification of bioactive L-arginine in their exterior region. The lipid cores of these biomimetic SLNs contained cacao butter (CB) and tripalmitin varying between 0% and 7%. Effects of lipid composition, L-arginine coverage, and electromagnetic field (EMF) on the electrical properties of the novel SLNs were investigated. The morphological micrographs revealed that the particle size distribution of the spherical SLNs was quite uniform. Based on small-angle X-ray scattering of the SLNs, thickness of the external layers was about 4.5 nm. An increase in the percentage of CB in the emulsified fluids increased average diameter and charge of the SLNs in general. An increase in the percentage of CB however decreased particle softness. In addition, a higher fraction of the surface coverage of L-arginine yielded a higher average diameter and softness of the SLNs. On the contrary, an increase in the surface coverage of L-arginine on the SLNs decreased charge in the peripheral zone. In regard to electromagnetic regulation, the exposure to EMF reduced charge and increased softness of the SLNs. From biomedical aspect, these SLNs could be potentially applied to drug entrapment and targeted delivery in preclinical trials. (C) 2009 Elsevier B.V. All rights reserved.