Ph.D. thesis: Mudassar Mumtaz Virk

How about developing a technology that allows the doctor to release drugs from biocompatible nanocapsules remotely through the press of a button? Dr. Mudassar Mumtaz Virk had a closer look at the science behind triggering drug release by magnetic actuation in the Ph.D. thesis he recently defended.

Nanomaterial-based drug delivery systems are currently in an early stage of development, but they are expected to have a revolutionary impact on health care due to their capability of selectively treating targeted cells while reducing collateral toxicity to healthy cells. Stimuli-responsive drug delivery systems, which can release their cargo in response to an internal or external stimulus, is one way in which this can be achieved.

The most popular and well-researched drug delivery vehicles are based on lipid and polymer amphiphiles that allow encapsulating the drug in nanocontainers by self-assembly. However, existing systems show poor release characteristics or alternatively are not sufficiently robust or traceable in the body.

In his Ph.D. thesis, Dr. Virk’s goal was to investigate the properties and release kinetics of lipid- and polymer-based delivery systems, including the properties of these membranes that make triggered release possible. The thesis is an experimental study on how to combine the best properties of polymer and lipid delivery systems, respectively, to optimize stability and fast triggered release.

The primary focus is on how magnetic nanoparticles can be used to change the permeability of lipid, polymer, and hybrid vesicle membranes in response to heating via magnetic fields. It was, e.g., demonstrated that release at any desired rate could be achieved in realistic conditions through inducing a local phase transition in the membrane but keeping the vesicles intact.

It was also demonstrated how the membrane properties influence release through lipase degradation, intrinsic to the body. Also, that hybrid membranes could eventually combine stability and controlled release.

The thesis is available (shortly) through the BOKU library service.