(7dl) Smart Magnetic Nanomaterials for Sustainable Applications in Biomedicine and Catalysis

Authors: 
Perera, A. S. - Presenter, University College London
Research Interests:

Magnetic nanomaterials are gaining steadfast attention from scientists, as quintessential components in a vast array of fields from heterogeneous catalysis to medicine. In particular, biomedical applications such as drug delivery, microfluidics, and tissue engineering that incorporate magnetic nanoparticles (MNPs) have become prominent, in recent years. Hybrid composite materials that combine organic and inorganic materials, together with magnetic components, offer enormous possibilities in developing new and enhanced biomedical practices and devices.

Magnetic scaffolds consisting of composites of hydrogels incorporated with magnetic nanoparticles, are currently gaining prominence in tissue engineering. This is due to the enhanced cell-compatibility properties introduced by the magnetic component such as increased cell adhesion, penetration and viability, as well as unique chemical, physical and mechanical properties. Great strides in this area have been made in bone regeneration, as magnetic composite scaffolds seem to significantly increase osteoblast integration and proliferation compared to the non-composite scaffolds. Another significant factor is that such scaffolds can either be actuated or stimulated using an external magnetic field, which can be greatly beneficial for targeted/triggered tissue engineering or drug delivery. However, due to the limitations in bio-stability and cost-effectiveness, such magnetic-polymer actuators have not yet been transformed into real-world applications.

Building on the above premise, a novel technique for fabrication of magnetic hydrogel actuators have been developed. These materials comprise of an organic polymer and Fe3O4 MNPs, and form a biocompatible platform, targeting multiple biomedical applications. The magnetic hydrogel has customizable physical and mechanical properties achieved via variation of polymer and MNP concentrations. Due its biocompatibility, biodegradability, facile synthesis, cost-effectiveness, scalability and self-healing properties, this material has the potential to be used in a vast range of biomedical applications, including implants, support materials, microfluidics, self-healing scaffolds and adaptive artificial muscles.

These magnetic polymeric composites have led to the development of a platform technology, and have generated multiple spin-off projects, including the fabrication of magnetic fibers, foams and 3D printed materials, all with actuation ability, coupled with biocompatibility. They are shown to be excellent vehicles for controlled drug release, due to their ability to respond to external magnetic fields. This technology is patent pending, and will continue to create multiple research opportunities as a result of their versatile nature and the ability to be synthesized in a facile, energy-efficient manner.

Another field that benefits significantly from the unique properties of MNPs is heterogeneous catalysis. Iron/iron(III) oxide core-shell nanoparticles are highly valuable catalysts, with industrial appeal. Sulfonic acid catalyzed core-shell nanoparticles were used as a highly selective catalyst to hydrolyze cellulose into glucose. A statistical technique was used to systematically optimize the reaction conditions of the above. The statistically-guided optimization led to high selectivity toward glucose, while production of 5-HMF and other monosaccharides were decreased. Reduction of 5-HMF is particularly significant, as it is toxic to yeast, which are used industrially, to convert cellulose degradation products into ethanol. The catalyst was found to be highly stable and reusable, due to its magnetic property, thus, leading to a potential sustainable, technology for conversion of plant matter into ethanol.

The above is a selected summary of work from my post-doctoral research, conducted at University College London (advisor Prof Marc-Olivier Coppens) and my PhD at Kansas State University (advisor Prof Stefan H. Bossmann). My future research plans include development of novel nanomaterials via sustainable routes for biomedical applications, and heterogeneous catalysis.

Teaching Interests:

My teaching experience includes conducting lectures, at graduate and undergraduate levels, and lab classes, in areas of physical organic chemistry, synthetic organic chemistry, organometallic chemistry and general chemistry. I am interested in further expanding my scope of teaching into thermodynamics, process engineering and nanomaterials engineering. My teaching philosophy is based on promoting the following principles: 1) generating a true enthusiasm for science, 2) effective communication between student and teacher, 3) bridging the gap between lecture and lab classes and 4) real world applications. I also strongly believe that undergraduate and graduate teaching must go hand in hand with public engagement and outreach. I have been a volunteer for multiple outreach programs that aim to promote interest in STEM disciplines at the middle and school levels. I have also been an invited speaker at multiple science festivals and events in London, aimed at educating the general public on current research.