Look-up table for assessment of iron content in Magtrace® samples based on Sentimag®

Following the administration of a magnetic tracer (Magtrace®, Endomagnetics Ltd. UK), the Sentimag® device (Endomagnetics Ltd. UK) is employed as a handheld magnetic tool to identify the initial draining lymph node(s) originating from a primary tumour, commonly known as the sentinel lymph node (SLN). The evaluation is primarily qualitative and does not yield information regarding the quantity of iron tracer present in the SLN. A look-up table (LUT) dataset has been created exclusively for the Sentimag® handheld probe (Endomagnetics ltd. UK). This LUT serves the purpose of quantifying the accumulation of Magtrace magnetic tracer within SLN through the utilisation of magnetic readout counts.Data collection involved six repeated magnetic measurements on 15 Magtrace® samples, each with a total volume of 35µL. The iron content of these samples ranged from of 0 to 504 µg, encompassing the following amounts: 0, 1.12µg, 5.04µg, 10.08µg, 28µg, 50.4µg, 100.8µg, 120µg, 140µg, 182µg, 210µg, 252µg, 280µg, 420µg, and 504µg. For data analysis, a first-order polynomial-fit method was employed to interpolate the magnetic counts and iron content by a custom-made software (Matlab version R2021b, Mathworks).The LUT is available as an Excel file, comprising four columns that encompass the outcomes of the interpolation process for various settings (1, 2, and 3).These columns consist of the iron content expressed in µg (column A) and and the relating counts for setting 1, 2 and 3 in the respective columns B, C and D. Moreover, the file includes a visual representation in the form of a figure, depicting the plotted data derived from the measured values as well as the fitted data resulting from the analysis.