title: Mechanical stability analysis of carrageenan-based polymer gel for magnetic resonance imaging liver phantom with lesion particles.
abstract: Medical imaging is an effective technique used to detect and prevent disease in cancer research. To optimize medical imaging, a calibration medium or phantom with tissue-mimicking properties is required. Although the feasibility of various polymer gel materials has previously been studied, the stability of the gels' properties has not been investigated. In this study, we fabricated carrageenan-based polymer gel to examine the stability of its properties such as density, conductivity, permittivity, elastic modulus, and [Formula: see text] and [Formula: see text] relaxation times over six weeks. We fabricated eight samples with different carrageenan and agar concentrations and found that the density, elastic modulus, and compressive strength fluctuated with no specific pattern. The elastic modulus in sample 4 with 3 wt. % carrageenan and 1.5 wt. % agar fluctuated from 0.51 to 0.64 MPa in five weeks. The [Formula: see text] and [Formula: see text] relaxation times also varied by 23% to 29%. We believe that the fluctuation of these properties is related to the change in water content of the sample due to cycles of water expulsion and absorption in their containers. The fluctuation of the properties should be minimized to achieve accurate calibration over the shelf life of the phantom and to serve as the standard for quality assurance. Furthermore, a full liver phantom with spherical lesion particles was fabricated to demonstrate the potential for phantom production.
authors.affiliation: University of Toronto , Smart and Adaptive Polymer Laboratory, Department of Mechanical & Industrial Engineering, 5 King's College Road, Toronto M5S 3G8, Canada.
authors.forename: Eunji
authors.initials: E
authors.lastname: In
authors.affiliation: University of Toronto , Smart and Adaptive Polymer Laboratory, Department of Mechanical & Industrial Engineering, 5 King's College Road, Toronto M5S 3G8, Canada ; University of Toronto , Department of Materials Science and Engineering, Wallberg Building, 184 College Street, Toronto M5S 3E4, Canada ; University of Toronto , The Institute of Biomaterials and Biomedical Engineering, 164 College Street, Toronto M5S 3G9, Canada.
authors.forename: Hani
authors.initials: H
authors.lastname: Naguib
authors.affiliation: University of Toronto , Department of Radiology, 263 McCaul Street, Toronto M5T 1W7, Canada.
authors.forename: Masoom
authors.initials: M
authors.lastname: Haider
keywords: MRI; T1 and T2 relaxation times; medical imaging; phantom; polymer gel; stability