Biophysical Society Thematic Meeting| Lima 2019

Revisiting the Central Dogma of Molecular Biology at the Single-Molecule Level

Poster Abstracts

30-POS Board 30 THE INTERFERENCE OF ORGANIC SOLVENTS IN THE CRYSTALLINE STRUCTURE OF NONIONIC CUBOSOMES Mayra C G Lotierzo 1 ; Barbara Malheiros 1 ; Bruna Casadai 1 ; Raphael D Castro 1 ; Giovana Firpo 1 ; Leandro R Barbosa 1 ; 1 USP, São Paulo, Brazil Cubosomes are nanoparticles composed of a specific combination of some types of amphiphilic lipids, such as phytantriol, and a nonionic polymer used as a stabilizer for the cubic phase. They have a high hydrophobic area and potential for the drug delivery system. Due of their unique structure, these nanoparticles possess the ability to incorporate highly hydrophobic drugs. A challenge for the encapsulation of hydrophobic molecules is the use of organic solvents in the sample preparation process. In this study we performed the Bottom-Up protocol for the production of cubosomes. To investigate the structural influence of the organic solvents, Small Angle X-ray Scattering (SAXS), Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) were used. The phytantriol cubosomes have a crystallographic cubic phase Pn3m with lattice parameter at ~ 6.83 nm and size of ~ 220 nm. Acetone presented interference in the structure of the nanoparticles in concentrations 1: 1 and 1: 2. Chloroform interacted with the nanoparticles, destroying them at even lower concentrations, from 1: 500. Ethanol destroyed the cubosome structure from the 1: 5 concentration. The octane presents a transition from cubic to hexagonal phase in concentration 1:35. DMSO interfered in the structure only at concentrations 1: 2 and 1: 1. All proportions presented were calculated by volume. The organic solvents tested are suitable for the encapsulation of hydrophobic drugs in the cubosome, but at high concentrations they destroyed the cubic structure of the nanoparticles.

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