[Determination of plasma lactoferrin by the "double sandwich" immunoenzymatic method in heterogeneous phase]

For the determination of lactoferrin in human plasma we describe a double-sandwich immunoenzymatic assay in 3 steps using tubes as the solid phase. The analytical performances are acceptable. Within-run and between-run CVs are respectively 4% and 13%, the lower limit of detection is 8 micrograms/l. Sensitivity and specificity are good. The influence on lactoferrin concentration of time elapsing from blood sampling to separation of plasma from cells was studied in order to define the optimal conditions of storage and centrifugation. The range of concentration obtained on 22 healthy adults lies between 59 and 345 micrograms/l.