Plasma Peptide Levels Measurement

Plasma subfatin, preptin, and betatrophin levels were examined using the Human subfatin, preptin, betatrophin ELISA Kit (Sunred Biological Technology, Shanghai, China) in a plate-washing -incubation CombiWash device (Human Diagnostics, Wiesbaden, Germany) in accordance with the study procedures defined in the kit catalogue. Absorbance measurements were taken with a Chromate 4300 Microplate Reader (Awareness Technology, Palm City, USA).
These kit companies in their kit catalogs stated that the minimum detection limit of subfatin was 0.042 ng/mL. The intra-assay and inter-assay coefficients of variation for plasma subfatin were < 10% and < 12%, respectively. The minimum detection limit of preptin was 5.125 ng/L (0.0051 ng/mL). The intra-assay and inter-assay coefficients of variation for plasma preptin were < 10% and < 12%, respectively. The minimum detection limit of betatrophin was 7.334 ng/L (0.0073 ng/mL). The intra-assay and inter-assay coefficients of variation for plasma betatrophin were < 10% and < 15%, respectively. Preptin and betatrophin concentration units are given in ng/L and subfatin in ng/mL by the manufacturer. However, to facilitate the comparison between parameters, all units were converted to ng/mL [20 (link)].