The optimum parameters for SWV measurement were found in preliminary trials (data not shown) to be a pulse amplitude of 0.15 V, square wave frequency of 30 Hz, and a step height of 0.005 V for scanning the potential between −0.2 V and 0.8 V vs. Ag/AgCl, and so these parameters were used throughout this study. Protein precipitation using TCA was used for serum sample preparation [51].The sample was vortexed for 5 min following TCA addition to 0.6 M followed by centrifugation at 1073 rcf for 10 min and harvesting of the supernatant.