Hybrid complexes of polyelectrolytes and magnetite for controlled release of Amoxicillin

Author(s)

Pedro Vinicius de Assis Bueno

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
• Defense date: 2018-08-10

Examining board members

Denise Freitas Siqueira Petri; Luciano Caseli; Irene Satiko Kikuchi

• Advisor: Denise Freitas Siqueira Petri

Abstract

New biocompatible systems for biotech applications are relevant not only from a technological point of view, but also for scientific advances. The present project aimed at the creation and characterization of thin films (thickness up to 100 nm) or micrometric patches (thickness of 50 µm to 100 µm) formed by the deposition of xanthan gum (GXT), poly (dimethyl diallyl ammonium chloride) (PDDA), bovine serum albumin (BSA), and magnetite nanoparticles (NPM). The incorporation of amoxicillin (Amox), a widely used antibiotic against many infections, in the films was performed during the formation of the systems. Thin films were characterized by means of ellipsometry and atomic force microscopy. In solution, favorable interactions between Amox and BSA were evidenced by substantial changes in the secondary structure of BSA, as revealed by circular dichroism spectra. Patches of GXT and GXT/NPM/BSA were immersed into Amox solution at 2 g/L, leading to the Amox incorporation of 10 ± 3 and 17 ± 4 µg/cm3, respectively. The patches characterization included Fourier Transform Infrared vibration spectroscopy in the attenuated total reflectance mode (FTIR-ATR), scanning electron microscopy (MEV), sorption measurements and inductively coupled plasma optical emission spectrometry (ICP-OES). The incorporation of 0.2 wt% of Fe3O4 in the patches and their exposure to an external magnetic field, allowed the total in vitro release of Amox, at pH 5.5 and 0.02 mol/L NaCl, following the behavior quasi-Fickian. Amox diffusion from GXT/NPM/BSA patches in agar containing Staphylococcus aureus and Escherichia coli led to a considerable zone of inhibition. Inhibition of E. coli growth was particularly efficient under the effect of external magnetic field. (AU)

• FAPESP's process: 16/08750-7 - Hybrid complexes of polyelectrolytes and magnetite for control release of amoxycillin
• Grantee: Pedro Vinicius de Assis Bueno
• Support Opportunities: Scholarships in Brazil - Master