Chromogenic peptide substrate for urokinase-type plasminogen activator (uPA / PLAU): L-pyroglutamyl-glycyl-L-arginine-p-nitroanilide hydrochloride (pyroGlu-Gly-Arg-pNA · HCl), Mw 499, supplied lyophilised at 97% purity (HPLC), 100 mg. Cleavage of the Arg–pNA bond by urokinase releases free p-nitroaniline, which is followed photometrically at 405 nm, giving a continuous, quantitative readout of uPA amidolytic activity. Use for enzyme activity determination, potency assignment and inhibitor screening — the functional counterpart to the human urokinase standard cat. 840 and to the anti-uPA antibodies cat. 168, cat. 335 and cat. 855.
SPECIFICATIONS
Catalogue number: 270 | Product: Urokinase (uPA) colorimetric substrate
Chemical name: L-pyroglutamyl-glycyl-L-arginine-p-nitroanilide hydrochloride (pyroGlu-Gly-Arg-pNA · HCl)
Molecular weight: 499
Purity: 97% (HPLC)
Format: lyophilised | Package size: 100 mg
STORAGE / RECONSTITUTION
Dissolve in distilled water.
Lyophilised substrate: ships at ambient temperature; store for 2 years at −20 °C, dry and protected from light.
Reconstituted substrate: store at +4 °C for up to 2 months.
Avoid repeated freeze-thaw cycles of reconstituted material.
APPLICATIONS
- Urokinase amidolytic activity assay: activity is measured as the increase in optical density at 405 nm at 37 °C (0.025 min−1 in 0.14 M NaCl, 0.01 M sodium phosphate pH 7.5, with 0.2 mM substrate and 100 IU/mL urokinase).
- Potency assignment and lot-release testing of urokinase preparations, including the human urokinase standard cat. 840.
- Screening and IC50 determination for uPA inhibitors (amiloride analogues, small-molecule and peptidomimetic inhibitors).
- Kinetic characterisation (Km, kcat) of uPA and of uPA variants.
- Functional readout for pro-uPA activation and plasminogen-activator-system studies.
APPLICATION HIGHLIGHTS — HIGH-VALUE RESEARCH NICHES
- Tumour-invasion research: the uPA / uPAR axis is a validated prognostic marker and drug target in breast and other carcinomas.
- Fibrinolysis and thrombolysis: quantifying plasminogen-activator activity in plasma and cell-conditioned media.
- Antifibrinolytic and anti-invasive drug discovery: continuous, plate-readable inhibitor screening format.
- Quality control of recombinant and urinary urokinase batches.
- Complements immunoassay-based uPA quantification (antigen) with a true activity readout.
