Development Of Innovative Drug Delivery Systems Research Articles

Development of d,l-α-tocopherol acetate/zeolite carrier system: equilibrium study

The wide and efficient biomedical applications of zeolite materials provoked, in recent years, the development of a new trend in biomedical sciences and engineering, namely the development of innovative drug-delivery systems based on zeolite materials. The present study investigated a process for the development of a new antioxidant–carrier system, emphasizing on the extent of d,l-α-tocopherol acetate encapsulation in the framework of natural zeolite and on the mechanism of its sorption at equilibrium conditions. UV/Vis, FT-IR, SEM, and potentiometric analyses were conducted to provide data on the spectral, morphological, and physicochemical characteristics of a novel d,l-α-tocopherol acetate/zeolite carrier system. The experimental sorption equilibrium isotherms were described by ten mathematical models by means of non-linear analyses. The effect of pH on the absorption spectra of d,l-α-tocopherol acetate and on its adsorption behavior was studied. The maximum achieved equilibrium sorption capacity of zeolite toward the antioxidant was q max = 9.9 μg/mg. The integrative analyses of the values of the correlation coefficients and error functions together with the mode of the experimental and model isotherms established that Sips and Redhead models best represented the equilibrium sorption behavior of the studied system. The optimum pH for α-tocopherol encapsulation on zeolite was established to be pH 6.5–7.0.

Characterization and Stability of Nanostructured Lipid Carriers as Drug Delivery System

Recently more focus has been put to the development of innovative drug-delivery systems that includes polymer nanoparticles, emulsions and liposomes and solid lipid nanoparticles (SLNs). The SLNs have been proposed to be an alternative colloidal drug delivery system. The aim of this study was preparation and characterization of solid lipid nanoparticle (SLN) using varieties of emulsifier for encapsulation of the drug with poor water solubility. In these study four types of solid lipid nanoparticles were prepared based on different compositions of palm oil (S154) and lecithin (Lipoid 100) using the high pressure homogenization method. The SLN formulation had the following (palm oil+lecithin) compositions: SLN-01 (90 + 10%, respectively), SLN-02 (80 + 20%, respectively), SLN-03 (70 + 30%, respectively) and SLN-04 (60 + 40%, respectively). The SLNs were characterized and the optimum stability factors for one year storage determined. The parameters used to characterize the SLNs were particle size and polydispersity index (particle sizer), zeta potential (zetasizer), crystallinity (differential scanning calorimetry and wide angle X-ray diffraction), ultrastructure (transmission electron microscopy). Varying the palm oil and lecithin compositions resulted in SLNs of variable sizes and zeta potentials. The particle sizes of SLN-01, SLN-02, SLN-03 and SLN-04 were 298.40 +/- 11.80, 255.40 +/- 3.20, 145.00 +/- 3.39 and 273.00 +/- 86.50 nm, respectively, while the zeta potentials were -19.44 +/- 60.00, -19.50 +/- 1.80, -17.83 +/- 10.00 and -13.33 +/- 2.30 mV, respectively. Thermoanalysis and X-ray diffraction analysis showed that the SLNs had lower crystallinity than bulk lipid. The SLNs were generally round and uniform in shape under transmission electron microscopy. The SLN dimensional data suggested they had high quality physicochemical characteristics, which are conducive for the loading of poor water solubility drugs.

Cytotoxicity Effect of Solid Lipid Nanoparticles on Human Breast Cancer Cell Lines

Recently more focus has been put to the development of innovative drug-delivery systems that includes liposomes and solid lipid nanoparticles (SLNs). An in vitro study was conducted to determine the effect of solid lipid nanoparticle on the human breast cancer cell lines (MCF-7 and MDA-MB231). The SLNs based on palm oil were prepared using the high pressure homogenization method and were characterized by the particle size and polydispersity index (particle sizer), zeta potential (zetasizer), ultrastructure [transmission electron microscopy (TEM)] and MTT assay and natural red assay. Homogenization of solid lipid nanoparticles at 1000 bar for 20 cycles produced particles with 145.00±3.39 nm in size and zeta potential of -19.50±1.80 mv. The SLNs were generally round and uniform in shape. The cytotoxicity of the components of the SLN formulation was low: SLN with 1% oleyl alcohol displayed no significant cytotoxicity effect on breast cancer cells. In the light of these findings, SLN stabilized with 30% lecithin and 1% oleyl alcohol as nonionic co-surfactant in aqueous phase was found to be safe for cells and the acceptable for the incorporation lipophilic drugs.