A rapid enzymatic assay for total blood polyamines

We have designed a rapid, reliable enzymatic assay for total blood polyamines, as based on the combination of substrate specificity of polyamine oxidase (PAO) from Aspergillus terreus and putrescine oxidase (PUO) from Micrococcus rubens. Quinone dye, derived from hydrogen peroxide generated in the oxidation reaction, is measured spectrophotometrically at 555 nm, and total amounts of putrescine (Put), cadaverine (Cad), spermidine (Spd), and spermine (Spm) can be readily determined. The minimum detection limit is about 0.4 mumol/L whole blood. Bilirubin, hemoglobin, reducing substances, and anticoagulants show no apparent interference. Analytical recovery averaged 98.5%. Within-run and between-day precisions ranged from 1.02% (61.04 mumol/L) to 2.84% (13.07) and 1.54% (50.67) to 3.27% (14.74), respectively. Results obtained with this method and those by high-performance liquid chromatography (HPLC) (r = 0.955) or the enzymatic differential method (r = 0.944) correlated well. In our opinion, this method is superior to other assays being used to determine blood polyamines.