Tesis profesional presentada por Ricardo González Hidalgo [ricardo.gonzalezho@udlap.mx]

Miembro del Programa de Honores. Licenciatura en Nanotecnología e Ingeniería Molecular. Departamento de Ciencias Químico Biológicas. Escuela de Ciencias, Universidad de las Américas Puebla.

Jurado Calificador

Director: Dr. Miguel Angel Méndez Rojas
Presidente: Dra. Mónica Cerro López
Secretario: Dr. Ricardo Navarro Amador
Vocal: Dr. Felipe Córdova Lozano

Cholula, Puebla, México a 2 de diciembre de 2024.

Abstract

A system of Ni1-xZnxFe2O4 nanoparticles with varying Zn2+ content (x=0, 0.25, 0.5, 0.75) was synthesized via chemical co-precipitation and sintered at 1000°C to enhance magnetic properties. The nanoparticles were extensively characterized (XRD, SEM, EDX, Raman, FTIR, and magnetic hyperthermia studies), revealing crystalline sizes below 20 nm, except for x=0.25, which exhibited sizes of 25-28 nm. Secondary phases (hematite and nickel oxide) were detected in the x=0.25 sample, and while these were removed through acidic treatment to improve crystallinity, the ferrites containing impurities prior to the acidic treatment showed the best hyperthermia performance. This behavior is attributed to the presence of magnetic oxides, as confirmed by XRD analysis. Acid treatment increased nanoparticle stability, corroborated by DLS studies, and the x=0.75 sample demonstrated the best magnetic hyperthermia performance after treatment, likely due to lattice parameter rearrangements. Homogeneous nanofibers were fabricated via electrospinning, using the synthesized nanoparticles coupled with chitosan and PVA. Various component concentrations were tested, with the most suitable being 2.75% chitosan and 10% PVA. Additionally, initial efforts were made to create core-shell nanofibers using the same chitosan/PVA/ferrite nanoparticle core with a polymeric polycaprolactone shell. However, methodological constraints prevented their complete formation, and these challenges will be addressed in future research.

Keywords: Magnetic nanoparticles; Nanofibers; Magnetic Hyperthermia; Electrospinning; Nanomedicine.

Table of content

Acknowledgements

Chapter 1. Introduction

Chapter 2. Justification

Chapter 3. Objectives

  • 3.1 General objective
  • 3.2 Specific objectives

Chapter 4. Theoretical background

  • 4.1 Magnetic Nanoparticles - An Overview
  • 4.2 Magnetic ferrite nanoparticles
  • 4.3 Magnetic core-shell nanostructures - An Overview
  • 4.4 Specific applications
  • 4.5 Electrospinning process

Chapter 5. Methodology

  • 5.1 Synthesis of magnetic nanoparticles
  • 5.2 Carboxymethylation of chitosan
  • 5.3 Synthesis of PVA, Ch-PVA and CMC-PVA nanofibers
  • 5.4 Synthesis of Ch-PVA-MNPs nanofibers
  • 5.5 Synthesis of core-shell nanofibers
  • 5.6 Physicochemical characterization
  • 5.7 Magnetic hyperthermia study

Chapter 6. Results and discussion

  • 6.1 Physicochemical characterization of Ni1-xFe2O4 ferrite nanoparticles
  • 6.2 Physicochemical characterization of Ni1-xFe2O4 ferrite nanoparticles after acidic treatment
  • 6.3 Magnetic hyperthermia
  • 6.4 Carboxymethylation of chitosan
  • 6.5 Synthesis and characterization of nanofibers / nanocomposites

Chapter 7. Conclusions and Recommendations

References

Annex 1. Calculus of magnetic nanoparticles synthesis

González Hidalgo, R. 2024. Synthesis and characterization of Ni1-xZnxFe2O4-chitosan-PVA nanofibers and evaluation of their performance as a magnetic hyperthermia agent. Tesis Licenciatura. Nanotecnología e Ingeniería Molecular. Departamento de Ciencias Químico Biológicas, Escuela de Ciencias, Universidad de las Américas Puebla. Diciembre. Derechos Reservados © 2024.