Milliplex xmap luminex assay

Glucose was determined using a blood glucose meter (Accu-Chek, Roche, Basel, Switzerland). Plasma concentrations of total cholesterol (Roche Diagnostics Ltd., Rotkreuz, Switzerland), triglycerides (Roche Diagnostics Ltd., Rotkreuz, Switzerland) and non-esterified fatty acids (Wako Pure Chemical Industries, Osaka, Japan) were measured at the Adelaide Research Assay Facility using a COBAS Integra 400 analytical system (Roche Diagnostics Ltd., Rotkreuz, Switzerland). The minimum detection limit of the assay was 0.1 mmol/L for total cholesterol and triglycerides and 0.05 mmol/L for non-esterified fatty acids. The intra-assay coefficients of variation were 4.3% (total cholesterol), 6.1% (triglycerides) and 11.0% (non-esterified fatty acids). The leptin concentration was determined using the Milliplex xMAP Luminex Assay (Merck Millipore, Temecula, CA, USA). The minimum detection limit for leptin was 0.04 ng/mL and the intra-assay coefficient of variation was 8.3%.

The plasma gastric inhibitory peptide (GIP) concentrations were determined, in duplicate, using the Milliplex xMAP Luminex Assay according to the manufacturer’s instructions (Catalogue No.: MMHE-44K; Merck Millipore, Temecula, CA, USA). The procedures of the assay were followed strictly according to the manufacturer’s instructions and all plasma samples were evaluated neat (40 μL). The minimum detection limit for GIP was 0.001 ng/mL and the intra-assay coefficient of variation was 8.43%.