1 research outputs found
Nanoparticles for tumour diagnostics
X-ray fluorescence techniques have proven beneficial for identifying and quantifying
trace elements in biological tissues. A novel approach has been developed that employs
x-ray fluorescence with an aim to locate the presence of nanoparticles, such as gold,
which are embedded into tissues. The nanoparticles can be functionalised to act as
markers for tumour characteristics to map the disease state, and then imaged to inform
cancer therapy regimes. The uptake of nanoparticles by cancer cells could also enable
detection of small clusters of infiltrating cancer cells which are currently missed by
commonly used imaging modalities. The novel system, consisting of an energy
resolving silicon drift detector with high spectral resolution, and a synchrotron source,
showed potential in both quantification of and sensitivity to nanoparticle concentrations
typically found in tumours. A linear relationship between fluorescence intensity and
nanoparticle concentration was found down to 0.001 mgAu/ml, the detection limit of
the system. A successful translation using a more clinically available bench-top x-ray
tube was demonstrated, and found not to degrade the linearity or detection limit. The
achieved system sensitivity suggests clinical usefulness in measuring tumour uptake in
vivo. A set of bio-phantoms consisting of collagen type 1 gel, populated with colorectal
cancer cells (HT29) and healthy murine fibroblast cells (3T3) that have been incubated
with gold nanoparticles (GNPs), were created. The bio-samples were successfully used
to (i) demonstrate GNP uptake in cells, and (ii) demonstrate the use of the novel benchtop
system in measuring GNP uptake in cells. Translation to a 2D imaging technique
was undertaken, using polycapillary optic technology to acquire positional information
of gold XRF emissions, and energy resolving single channel and pixellated detectors.
The GNP-imaging capabilities of the XRF technique were demonstrated using Perspex
phantoms incorporating different GNP concentrations. Details of phantoms with
concentrations as low as 0.025 mgAu/ml have been successfully imaged, with potential
to image lower concentrations. It can be inferred from feasibility data collected that the
x-ray fluorescence technique can be combined with x-ray diffraction methods to form a
novel multi-modality system that is sensitive to GNP distribution and can discriminate
biological tissue. Future work will develop this combined system to locate tumours and
provide information on tumour characteristics