Eco-Friendly Bioimpedance Fat Phantom: PVA emulsion Mimicking the Electrical Properties of Living Tissue at Low...

This paper presents the development of a fat phantom using an emulsion of polyvinyl alcohol (PVA) and beeswax, filled with activated carbon to replicate the electrical and mechanical properties of living adipose tissues. The characterisation and optimisation of these mixtures were achieved by preparing samples with different types and concentrations of wax and varying concentrations of activated carbon. The electrical properties of the samples were measured using bioelectrical impedance spectroscopy (BIS) over a low-frequency range (1 kHz to 1 MHz). Standardised two-electrode measurement cells were employed to enable comparisons with literature data. PVA can be cross-linked via freeze/thaw cycles to form polyvinyl alcohol cryogel (PVA-C), a hydrogel with mechanical properties similar to those of living tissue. The PVA-wax emulsions also formed a hydrogel after undergoing a freeze/thaw cycle. In the initial phase of this study, the properties of PVA-C were compared with those of PVA-C containing activated carbon, which was identified as a suitable candidate for mimicking the electrical properties of living fat. The subsequent phase focused on developing a PVA-wax emulsion to reduce the permittivity of the PVA-C at high frequencies, thereby approaching the permittivity of living fat. The mechanical properties of the resulting hydrogel were found to closely resemble those of living fat.Clinical Relevance-This established a methodology for developing an adipose tissue phantom for use in validating bioelectrical impedance spectroscopy (BIS) sensors in medical applications.