Nanoparticles as Contrast Agents in High Frequency Ultrasound Imaging for Pathology Diagnostics

With high cancer survival rates been so often dependent on earlier detection, molecular imaging presents a particularly useful approach in cancer screening. However, the current imaging technology required to carry out such detailed examinations often involves the use of harmful radiation and/or very expensive equipment. Therefore, the demand for a new non-invasive and inexpensive imaging modality that is safe enough to allow for more frequent screening to take place (both before and after cancer treatment) continues to be of great importance (Buccafusca, Proserpio, Tralongo, Rametta Giuliano, & Tralongo, 2019).

High frequency ultrasound imaging is a non-invasive, non-ionising, portable and inexpensive imaging modality that can be used in conjunction with small diameter nanoparticles (10-100 nm) to move ultrasound imaging from the restrictions of the blood pool into small tumour masses.

Silica nanoparticles between 10-100nm in diameter were employed in this work to investigate the specific acoustic properties of silica nanoparticle material. The particle size distribution of the particles within a tissue mimic was characterised and acoustic measurements were taken using a 50MHz broadband transducer. The ultrasound attenuation data acquired in this work was not indicative of any relationship between the specific material properties of the silica nanoparticles employed and high frequency ultrasound. However, the development of the early stage experimental design outlined in this work provides a basis for future research and development in nanoparticle size characterisation within tissue mimics.