Preparation of Magnetoliposomes with a Green, Low-Cost, Fast and Scalable Methodology and Activity Study against S. aureus and C. freundii Bacterial Strains

Rosangela Silva,Luciano R S Lara,Jacqueline Takahashi,Humberto Stumpf,Ângela Andrade,Tulio Matencio,Henriete Vieira,Junnia Oliveira,Jorge López,Rosana Domingues

doi:10.21577/0103-5053.20180144

Abstract

A novel, fast, low-cost and scalable methodology to prepare stable magnetoliposomes (MGLs), without the use of organic solvents, is described. The concept of the work is based on the dual use of soy lecithin associated to a new liposome preparation methodology. Soy lecithin was used to coat the nanoparticles of magnetite (Fe3 O4 @lecithin) and for encapsulation of Fe3 O4 @lecithin (Lip-Fe3 O4 @lecithin). Liposomes with size less than 160 nm, polydispersity index of 0.25 and zeta potential of -41 mV, were prepared with the use of autoclave and sonication. The liposomal formulations containing magnetite and stigmasterol (Lip-Fe3 O4 @lecithin, Lip-Stigma and Lip-Stigma-Fe3 O4 @lecithin) were shown to be promising for the application as antibacterial. The liposomal formulation and magnetite were characterized by the following techniques: conventional and high-resolution transmission electron microscopy (TEM/HRTEM), energy-filtered transmission electron microscopy (EFTEM), proton nuclear magnetic resonance (1H NMR), Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRPD), dynamic light scattering (DLS) and zeta potential. The Lip-Fe3 O4 @lecithin had a minimum inhibitory concentration (MIC) of 8.4 µg mL-1 in the presence of 200 Oe magnetic field against S. aureus.

Highlights

The disordered use of antibiotics has increased the inefficiency of several classes of antibacterial agents in combating microorganisms called multiresistant
The first step in preparing the MGLs involved the synthesis of magnetite through a modified co-precipitation method previously described[31,32] and the modification of its surface in a one-pot reaction is shown in Figure 1 to prepare Fe3O4@lecithin
Tests for S. aureus and C. freundii inhibition were done against the liposomes samples prepared under three different conditions: (i) 25 °C for 30 min (WMF25); (ii) oven heating at 41 ± 1 °C for 30 min (WMF41); and (iii) magnetic field for 30 min at 41 ± 1 °C (MF41)

Summary

Introduction

The disordered use of antibiotics has increased the inefficiency of several classes of antibacterial agents in combating microorganisms called multiresistant. This methodology involves hydrating the soy lecithin in an autoclave at 120 °C for 15 min, cooling to 4 °C, liposome size reduction, encapsulating stigmasterol and/or Fe3O4@lecithin and using ultrasound tip.

Results

Conclusion