Phosphate buffered saline (PBS) solution is a balanced salt solution employed for cell manipulation in cell culture experiments. In this work, PBS is used as base component for making liquid tissue-equivalent materials, also known as phantoms. For this purpose, the dielectric properties of PBS and other balanced salt solution and cell culture media used in cell culture experiments are measured at different temperatures (9 ∘ C, 21 ∘ C, and 37 ∘ C) with an open-ended coaxial probe. Moreover, the two-pole Cole–Cole model of all these measured media at the mentioned temperatures is computed. As a result of the similar dielectric losses of these media to biological tissues, the simplest one (PBS) was chosen to make tissue phantoms. The proposed phantoms are mixtures of PBS, distilled water, sodium chloride, and seed oil-based non-ionic surfactant and they are electrically characterized at 21 ∘ C using an open-ended coaxial probe. These phantoms are biodegradable, safe, low cost, ease-to-prepare, and time-stable over a broadband frequency range (400 MHz–6 GHz). Moreover, all measured data is available in an online open access repository.