Lh. Stanker et al., DEVELOPMENT OF A MONOCLONAL ANTIBODY-BASED IMMUNOASSAY TO DETECT FUROSEMIDE IN COWS MILK, Journal of agricultural and food chemistry, 44(8), 1996, pp. 2455-2459
Furosemide is a potent diuretic drug used in both human and veterinary
medicine. High-performance liquid chromatographic methods (HPLC) were
developed to detect furosemide in blood and urine samples. Recently,
immunoassay kits have appeared to measure furosemide; these were devel
oped for the race horse industry where furosemide is used to treat epi
staxis. In dairy cattle, furosemide is used for treatment of physiolog
ical parturient edema and there is a 48-h withdrawal period before mil
k from treated animals can be used. We report here the development of
a monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA)
for detecting furosemide in milk. In addition, we report on the develo
pment of an HPLC method for detection of furosemide in milk that is an
adaptation of published methods for its detection in serum and blood.
Unlike the HPLC method, no sample preparation is necessary for the EL
ISA. Raw milk is added directly into the assay, or if needed, it is di
luted with assay buffer. The immunoassay had a lower limit of quantifi
cation of 2 ppb and a lower limit of detection of approximately 0.5 pp
b. Good correlations were observed between the HPLC and ELISA methods
when samples with both incurred and spiked furosemide residues were an
alyzed.