Total Collagen/Hydroxyproline Assay Kit

Cayman's Total Collagen/Hydroxyproline Assay Kit provides colorimetric-based methods for measuring collagen/hydroxyproline in tissue, serum, and urine. Prior to beginning the assay, collagen is hydrolyzed to individual amino acids. Hydroxyproline, found almost exclusively in collagen, makes up 11.3 to 15% of collagen 1 and collagen 3, respectively, by mass of the amino acid composition.¹ In this assay, hydroxyproline is oxidized by Hydroxyproline Reagent 1 to a pyrrole intermediate, which reacts with Hydroxyproline Reagent 2 to create a chromophore with peak absorbance at 560 nm. Both hydroxyproline and collagen standards are included. It is only necessary to use the standard that best fits the needs of your assay.

In studies where hydroxyproline measurement is relevant (i.e., collagen metabolism or biosynthesis) the hydroxyproline standards may be used. The hydroxyproline standards may also be used to calculate collagen levels in appropriate samples by assuming hydroxyproline makes up 11-15% of the amino acid content of collagen by mass. For a direct measurement of collagen, the collagen standard may be used. The collagen standard is hydrolyzed along with the samples to give hydroxyproline.

The range of this assay is 0.02-5 µg for collagen and 0.006-3 µg for hydroxyproline with lower limits of quantification (LLOQ) of 0.5 and 0.047 µg for collagen and hydroxyproline, respectively.

Needed but not supplied: Please download the kit booklet to verify if UltraPure Water (Milli-Q or equivalent) or any other components are needed for this assay.

WARNING This product is not for human or veterinary use.

1. Cissell, D.D., Link, J.M., Hu, J.C., et al. A modified hydroxyproline assay based on hydrochloric acid in Ehrlich’s solution accurately measures tissue collagen content. Tissue Eng. Part C Methods 23(4), 243-250 (2017).

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