Impact of high temperatures on enzyme-linked immunoassay (ELISA) performance for leptin measurements in human milk stored under varied freeze/thaw conditions

Our aim is to provide researchers
with information to make informed decisions regarding use of ELISAs that arrive
in suboptimal conditions as well as potential effects on assay measurements. Due
to unexpected shipping conditions from the manufacturer, leptin ELISA kits
arrived at our university laboratory in a warm condition (76.3°F/24.6°C), well
above the 2-8°C temperature conditions recommended by the manufacturer. Since
no data was available on the effects of high temperature exposure during
transportation on the performance of this commercial assay, we
opportunistically assessed assay performance with human milk measurements due
to the growing importance of leptin on lactation and breastfeeding
investigations as well as the ever-present risk of in-transit high temperature
exposure. We found that assay kit exposure to high temperature during shipping
resulted in sample results that were significantly different from temperature-controlled
kits despite similar standard curve performance.