Physical Characterization of Polyethylene Glycol Modified by Solid Lipid Nanoparticles for Targeted Drug Delivery

Solid lipid nanoparticles (SLNs) have been the most important in the field of nanotechnology these days, which have many enormous advantages, such as non-toxic compounds, high static physical capacity as well, carrying lipophilic drugs, and advantages like controlled drug release and targeted drug delivery with increased stability. Moreover, polyethylene glycol (PEG) has been used to increase the stability of the (SLNs). In this research describes the modification of the coating of (PEG) on the surface of (SLNs) to improve the efficiency of drug delivery to target cells in the body. However, (PEG-SLNs) were prepared by the ultrasonication/high-speed homogenization method. In contrast, the physical characterization of (PEG-SLNs) was studied by viscosity measurement at 37°C, which was developed by using stearic acid as a lipid matrix in ethanol as the dispersion medium. At that point, we noticed there was a decrease in relative viscosity (η r ) and dynamic viscosity (η) with the increasing of the weight of stearic acid, due to the result of the creation of (SLNs) that was coated by (PEG) which was modified by ultrasonication. Through Flory-Fox's theory treated the viscosity data to obtain the hydrodynamic radius (R H ), which was decreased from 100 to 50 nm, while the diffusion coefficient was (D) and mobility (μ) that has increased. Moreover, the zeta potential value was (ζ) > 30 mv, at 0.5 g cm -3 concentration of (PEG) with 2.5 g of stearic acid, this result was the best value of the stability of the solution. In this case, this study will use synthesized (PEG-SLNs) in the future for drug delivery to target cells in the body.