Copper colorimetric assay without deproteinisation serum plasma 3-500µg/dL Sentinel Diagnostics

Copper colorimetric assay without deproteinisation step manufactured by Sentinel Diagnostics

Divalent copper (Cu++) forms complexes with proteins. The major functions of copper metalloproteins involve oxidation-reduction; most know copper containing enzymes bind and react directly with molecular oxygen. In plasma approximately 95% of copper is bound to the alpha-2-globulin ceruloplasmin, an oxidase with ferroxidase activity. There is evidence that marginal copper deficiency is associated with heart disease, bone and joint osteoarthritis and osteoporosis. A decreased level of copper also results in decrease antioxidant protection.

This copper kit uses a pH 4.7 buffer system, in these conditions copper in the sample is released from ceruloplasmin (its carrier protein) and forms a stable, coloured complex with 3,5-DiBr-PAESA [4-(3,5-dibromo-2-pyridylazo)-N-ethyl-N-(3-sulfopropanyl)aniline]. The colour intensity of this complex as measured at 570nm is proportional to the amount of copper in the sample. The Sentinel Copper kit comprises two reagents; Reagent 1 is supplied as 5x20ml (R1a) and 10 ascorbic acid tablets (R1b) (two tablets to be added to 1 vial of R1a buffer) and Reagent 2 a ready-to-use liquid. A ready-to-use liquid standard (1x10ml) is also included in the kit. This direct colorimetric Copper assay is standardised to NIST (National Institute of Standards and Technology) and has a range of 3-500µg/dL.

These reagents can be used to measure copper in serum or heparin plasma. The Sentinel Copper Kit is suitable for manual methods of determination as detailed on the accompanying pack insert and can also be automated. Reagents are stored at 2-8C and the on board stability is 45 days with a calibration interval of 14 days. The recommended QCs for this test are Clinical Chemistry Controls 16150 and 16250.