Shaquib Rahman Ansari: From design to application: Iron oxide nanoparticles for imaging and therapeutics in inflammatory and infectious diseases

Abstract

Superparamagnetic iron oxide nanoparticles (SPIONs) are a promising advancement in nanomedicine, demonstrating remarkable potential in both diagnostic and therapeutic applications. They can be magnetized in a magnetic field and do not show permanent magnetization, allowing precise localization within the body. Under an alternating magnetic field, SPIONs generate heat, which can be used for magnetic hyperthermia therapy against cancer or to trigger drug release. Diagnostically, they are widely used as contrast agents for magnetic resonance imaging (MRI), while magnetic particle imaging (MPI) is an emerging preclinical diagnostic technique using SPIONs as tracers.

Despite these promising applications, the clinical utility of SPIONs is hindered by challenges related to scalable and reproducible manufacturing. Focused efforts are also needed to improve MPI resolution. Moreover, the application of magnetic hyperthermia for treating inflammatory and infectious conditions remains relatively underexplored. Therefore, the primary objective of this thesis was to develop SPIONs tailored for imaging and therapy of inflammatory and infectious diseases through scalable manufacturing techniques. 

The first part of the study involved a systematic review to examine the most pertinent research on use of SPIONs for diagnosing and treating chronic inflammatory diseases. MRI was identified as the predominant application of SPIONs. However, there was limited exploration of MPI and magnetic hyperthermia for imaging and treating inflammatory diseases, respectively.

In the second project, a risk-based pharmaceutical quality by design approach was used to optimize SPIONs for magnetic hyperthermia. The effect of nanoparticle properties on MPI performance was systematically investigated in the third project. Additionally, these projects established flame spray pyrolysis as a scalable and reproducible technique, for synthesizing nanoparticles with complex stoichiometry for magnetic hyperthermia and MPI.

In final part of the study, SPIONs were incorporated into composites by scalable techniques, to improve the treatment of inflammatory and infectious diseases. SPIONs were incorporated in tablets with an anti-inflammatory drug, celecoxib. The drug solubility improved significantly through magnetic hyperthermia-induced in situ amorphization. SPIONs were also incorporated into microfibers, and heat dissipation from magnetic microfibers was used with doxycycline against methicillin-resistant Staphylococcus aureus. This resulted in substantial reduction in bacterial growth compared to using the drug alone.

This thesis introduced systematic exploration of SPION properties and their functional performance, established a scalable synthesis technique for their production, and developed novel systems for wider adaptation of SPIONs in biomedical applications.