The knowledge of the peptide Hepcidin-25 has evolved cysteine rich antimicrobial peptide to master iron regulator. We have observed the move from measurement in urine to measurement in blood and translation from MALDI to ESI with high resolution MS systems. The additional Hepcidin isoforms (Hepcidin-20, Hepcidin-22 and Hepcidin-24), in conjunction with Hepcidin-25, have been extensively evaluated in correlation with a range of diseases. The utilisation of Hepcidin measurements in early childhood necessitates the measurements with minimal blood volumes and we aim for 50uL as the target serum volume for measurement. The correlation with metabolite profiles and Hepcidin isoform changes is required in order to utilise Hepcidin as part of the diagnostic panel for monitoring the onset of sepsis and development of rapid Hepcidin profiling methodologies.