Volumetric Absorptive Microsampling (VAMS) technology for IGF-1 quantification by automated chemiluminescent immunoassay in dried blood

For medical diagnostics and anti-doping analyses, insulin-like growth factor 1 (IGF-1) can be measured in serum using automated chemiluminescent immunoassays. The aim of this study was to assess the feasibility of using dried blood instead of serum to measure IGF-1 concentrations with an automated IGF-1 immunoassay and to evaluate if IGF-1 concentrations from dried capillary blood and serum were comparable. Blood samples (venous blood and capillary blood obtained from the arm skin using a device from Seventh Sense Biosystem) were collected with 20 μL Volumetric Absorptive Micro samplers (VAMS) (Mitra®, Neoteryx). These samplers offer the possibility of collecting a fixed volume of blood without perturbation by hematocrit. Starting from dried blood, an aqueous desorption in 0.9% NaCl was efficient to release IGF-1. The solution was directly analyzed on the automated IGF-1 immunoassay. IGF-1 concentrations after extraction from VAMS were lower than in serum (due to the dilution performed for the elution of IGF-1) but measurable for serum concentrations over 50 ng/mL. In addition, IGF-1 on VAMS was stable for at least one month at room temperature. Following adjustment for dilution, serum and dried blood IGF-1 concentrations were of the same order. However lower concentrations were obtained from the capillary blood in particular for high serum concentrations. In conclusion, a micro volume of dried capillary blood could be used to quantify IGF-1 with an automated chemiluminescent immunoassay. However, more data are needed to establish specific IGF-1 reference concentrations using dried capillary blood instead of serum.

Application of HBOCs electrophoretic method to detect a new blood substitute derived from the giant extracellular haemoglobin of lugworm

Manipulation of blood and blood components is prohibited in sports by the World Anti-Doping Agency (WADA). This includes the use of blood substitutes to increase oxygen transport, like haemoglobin-based oxygen carriers (HBOCs), which are compounds derived from haemoglobin. Despite their medical interest, the first generation of HBOCs had serious adverse effects and was abandoned. However, new studies are now exploiting the properties of marine worm haemoglobins, which circulate as giant extracellular complexes with high oxygen-binding capacities. HEMOXYCarrier® (HC), developed by Hemarina, is one of the most advanced and promising HBOCs, and HC may become a tempting doping tool for athletes in the future. Here, HC detection in plasma/serum was evaluated with the method used to detect the first HBOCs, based on electrophoresis and heme peroxidase properties. An HC-derived product was identified in human plasma up to 72 h after in vitro incubation at 37 °C. HC degradation also induced methemalbumin formation. After injecting HC at the effective dose of 200 mg/kg into mice, the HC-derived product was detected only for a few hours and no accumulation of methemalbumin was observed. Due to this limited detection window in vivo, measuring specific worm globin degradation products by mass spectrometry might be an alternative for future anti-doping analyses. Copyright © 2016 John Wiley & Sons, Ltd.