Pectin-decorated magnetite nanoparticles as both iron delivery systems and protective matrices for probiotic bacteria

FLORENCIA GHIBAUDO; VIVIANA CAMPO DALL´ORTO; ESTEBAN GERBINO; ANDREA GOMEZ-ZAVAGLIA; ESTEBAN GERBINO; ANDREA GOMEZ-ZAVAGLIA; GUILLERMO J. COPELLO; GUILLERMO J. COPELLO; FLORENCIA GHIBAUDO; VIVIANA CAMPO DALL´ORTO

COLLOIDS AND SURFACES B-BIOINTERFACES

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2019 p. 193 - 201

0927-7765

The goal of this work was to investigate biophysical stability of iron-pectin nanoparticles and analyze the feasibility of using them as delivery systems for the probiotic strain Lactobacillus plantarum CIDCA 83114. Iron oxide (Fe3O4) nanoparticles were synthesized from FeCl2.4H2O/0.5 M FeCl3.6H2O, and coated with citrus pectins.Their physico-chemical properties [FTIR, X-ray diffraction (XRD), ζ-potential, particle size, SEM, TEM] and theireffect on bacterial stabilization (viability after freeze-drying/storage, stability when exposed to simulated gastro-intestinal conditions) were assessed.XRD indicated the almost exclusive presence of magnetite crystalline phases. FTIR spectra confirmed the adsorption of pectin on magnetite nanoparticles surface. SEM and TEM images evidenced agglomerated nanoparticles, and a morphological surface change after adsorption of pectin. DLS and ζ-potential results proved the solvation of the ionizable groups in the hydrophilic network which induced chain expansion and agglomeration.Iron from nanoparticles demonstrated to be non-toxic for microorganisms up to 1.00 mg/mL. Simulated salivaand gastric solutions prevented nanoparticles from dissolution. The higher pH of the intestinal conditions (solvated -COO− and Fe-O− groups) facilitated the dispersion and partial dissolution of nanoparticles. Pectins adsorption on magnetite nanoparticles significantly enhanced electrostatic repulsion, which aided the solvation ofionized iron forms. The soluble species diffused out from the aggregates, being detected in the simulated intestinal fluid. Regarding bacterial viability, no decays were observed neither when pectin-decorated nanoparticleswere exposed to simulated fluids nor when stored at 4 °C for 60 days.The composites engineered in this work appear as adequate delivery systems for probiotic bacteria, whosetarget is the gut.