Reusable bi-directional 3ω sensor to measure thermal conductivity of 100-μm thick biological tissues

摘要: Accurate knowledge of the thermal conductivity (k) biological tissues is important for cryopreservation, ablation, and cryosurgery. Here, we adapt 3ω method—widely used rigid, inorganic solids—as a reusable sensor to measure k soft samples two orders magnitude thinner than conventional tissue characterization methods. Analytical numerical studies quantify error commonly “boundary mismatch approximation” bi-directional geometry, confirm that generalized slope method exact in low-frequency limit, bound its finite frequencies. The measurement device validated using control experiments within ±2% (liquid water, standard deviation) ±5% (ice). Measurements mouse liver cover temperature ranging from −69 °C +33 °C. results are independent sample thicknesses 3 mm down 100 μm agree with available literature non-mouse scatter.