Formulation, characterization and cytotoxicity studies of alendronate sodium-loaded solid lipid nanoparticles

• The formulated SLNs with Compritol showed particle size below 95 nm.
• SLNs exhibited a good stability profile at 4–9 °C temperature.
• A spherical and uniform shape of SLNs was confirmed with SEM.
• Biocompatibility of drug-loaded SLN was confirmed by cytotoxicity assay methods.

AimSolid lipid nanoparticles (SLNs) are novel drug delivery system for drug targeting in various routs of administration such as parenteral, oral, ophthalmic and topical. These carriers have some advantages such as high drug payload, increased drug stability, the possibility of incorporation of lipophilic and hydrophilic drugs, and low biotoxicity. In this study, alendronate sodium was used as a hydrophilic model drug and was incorporated into SLNs.MethodsHot homogenization method was used for preparation of alendronate sodium-loaded SLN formulations and the encapsulation efficiency of drug in SLNs was determined by ultrafiltration method using centrifugal devices. Scanning electron microscopy (SEM) was carried out to study the morphological behaviors of prepared SLNs like sphericity. Several cytotoxicity studies including MTT, DAPI staining and DNA fragmentation assays were used for biocompatibility assays.ResultsHigh drug encapsulation efficiency (70–85%) was achieved by drug determination through derivatization with o-phthalaldehyde. The physical stability of drug-loaded SLNs in aqueous dispersions was assessed in terms of size and drug leakage during two weeks. Scanning electron microscopy images showed spherical particles in the nanometer range confirming the obtained data from size analyzer. Several cytotoxicity studies including MTT, DAPI staining and DNA fragmentation assays as well as flow cytometry analysis confirmed the low toxicity of alendronate-loaded SLNs.ConclusionThe cost-efficient procedure, the avoidance of organic solvents application, acceptable reproducibility, ease of manufacturing under mild preparation conditions, high level of drug encapsulation, desirable physical stability and biocompatibility are the advantages of the proposed SLN formulations.

The schematic illustration of alendronate-loaded SLN preparation using hot homogenizing method.Figure optionsDownload as PowerPoint slide