Determination of Optimal Technological Conditions for the Process of Production a Liposomal Dosage Form of Cyphetrylin

Abstract

Introduction. The Laboratory for the development of dosage forms of the N. N. Blokhin National Medical Research Center of Oncology of the Ministry of Health of Russian Federation has developed a composition of an injectable liposomal dosage form based on soybean phosphatidylcholine, a hydrophobic analog of the hypothalamic hormone somatostatin − cyphetrylin, intended for the treatment of neuroendocrine tumors.Aim. Determination of optimal technological conditions for the process of obtaining a liposomal dosage form of cyphetrylin.Materials and methods. The study used the substance cyphetrylin synthesized in the of Chemical Synthesis Laboratory of the N. N. Blokhin National Medical Research Center of Oncology of the Ministry of Health of Russian Federation; soybean phosphatidylcholine S PC and polyethylene glycol-2000-distearoylphosphatidylethanolamine, produced by Lipoid GmbH (Germany); cholesterol ≥99 % (Sigma-Aldrich, Japan). For the preparation of phospholipid vesicles loaded with cyphetrylin and "empty", the methods of lipid film hydration with subsequent extrusion or homogenization of the dispersion of multi-layer liposomes were used. The obtained liposomal samples were evaluated by quality indicators − the effectiveness of the inclusion of cyphetrylin in vesicles, their average size and surface charge (zeta potential), the viscosity of the dispersion. To evaluate these characteristics, the methods of spectrophotometry, laser scattering spectroscopy, determination of the electrophoretic mobility of particles and viscometry were used.Results and discussion. It was found that the most suitable organic solvent for obtaining a solution of cyphetrylin and lipid components of the dosage form is chloroform. The duration of the drying period of the lipid film under vacuum to remove the residual solvent is determined by the ratio of the volume of the distillation flask used and the mass of its loading its loading. At the same time, hydration off the lipid film with water for injection should be carried out under conditions of low-pressure and room temperature. To obtain a dispersion of single-layer cyphetrylin liposomes of the required size, an extrusion method using nylon and polycarbonate membranes with a filter pore diameter of 0.22 and 0.2 um, respectively, was chosen.Conclusion. The optimal technological conditions for the process of obtaining a liposomal dosage form in the form of a dispersion of a hydrophobic analog of the hypothalamic hormone somatostatin − cyphetrylin are determined.

Keywords

• liposomes
• dosage form
• dispersion
• technological factors
• cyphetrylin
• soybean phosphatidylcholine