PhD Research

Background and Motivation

Early diagnosis and treatment are crucial issues in medicine. Disease causes alterations in the properties of biological fluids, indicating biomarkers associated with certain phenomena. These alterations lead to changes in the final desiccation patterns arising from droplet evaporation on surfaces. For example, a blood droplet acquired from a healthy individual would demonstrate different desiccation patterns compared to that acquired from a cancer patient. Hence, the investigation of the drying patterns of bio-fluid droplets is of great importance as it could provide the means for rapid medical diagnosis, offering the possibility to detect disease at early stages. This would reduce the cost of sample collection and storage, as well as hazards related to large amounts of biological fluids.

Overview

The aim of my thesis is to examine the effect of various parameters on the evaporative behaviour, internal flows and final desiccation patterns of micro-litre droplets of biological fluids, as a tool for the early diagnosis of bladder cancer. Many aspects affect the drying dynamics and the final desiccation patterns. Specifically, these include the fluid composition, substrate properties such as wettability and ambient conditions such as temperature and humidity.

My work includes the utilisation of Drop Shape Analysis (DSA) techniques for investigation of the temporal evolution of the contact angle, droplet radius and volume over time, combined with the acquisition of mass measurements via the use of microbalances. A large part of my work focuses on the acquisition of morphological data (via bright-field microscopy or Scanning Electron Microscopy) or topographical data (via Confocal Laser Scanning Microscopy) of the final dried patterns and image processing and analysis techniques for pattern classification. I also employ Energy Dispersive X-ray (EDX) Analysis techniques to probe the spatial distribution of components in the dried patterns. For the examination of the flows in the drying droplets, I use micro-Particle Image Velocimetry (micro-PIV) to visualise the internal flows and measure accurate flow velocities. Additionally, I use Infrared Thermography (IRT) for the investigation of the spatial variations of temperature in the drying drops.

Master’s Research

Background and Motivation

Breast cancer is one of the most frequent types of cancer manifesting in women, with approximately one million cases per year worldwide. This type of cancer arises from the abnormal proliferation and differentiation of breast epithelial cells, leading to malignancy. This imposes the need for the development of treatments that have the ability to destroy the malignant cells. However, current cancer treatments, such as chemotherapy, are not targeted, causing toxicity not only to the malignant cells, but to healthy cells as well.

Overview

The aim of this study was to develop a targeted treatment for breast cancer, via the use of Wharton’s Jelly mesenchymal stem cell-derived microparticles. Mesenchymal stem cell-derived microparticles can act as vehicles for the delivery of therapeutic miRNA to tumours, exploiting the ability of mesenchymal stem cells to selectively home in sites of inflammation. Specifically, we investigated the ability of microparticles to target cancer cells in vitro, elucidated the microparticle dose required for maximum in vitro response and probed the in vivo pharmacokinetic behaviour of microparticles in control and tumour-bearing animals.

This work included the culture of both mesenchymal stem cells and cancer cells, as well as in vitro techniques to isolate microparticles from mesenchymal stem cells. The microparticle population was identified via Fluorescence-Activated Cell Sorting (FACS). In vitro techniques were also employed to evaluate whether the microparticles had the ability to penetrate cancer cells, and the amount of cell death they could cause. This was done using Fluorescence Microscopy, Scanning Electron Microscopy and imaging techniques. In vivo biodistribution assays were performed to evaluate the toxicity and tumour-targeting ability of the mesenchymal stem cell-derived microparticles in mice.