Collagen Detection

ELISA Kits for type I and type II collagen quantification

Chondrex’s mission is to accelerate the rate of discovery in immunology research by providing scientists with high quality, reliable products. Chondrex provides Collagen Detection ELISA Kits for quantifying various species of type I and type II collagen, as well as total collagen detection.

Collagen Detection

The extracellular matrix (ECM) is a highly dynamic and complex three-dimensional structure composed of a macromolecule network including collagen, glycosaminoglycans (GAGs), elastin, fibronectin, and several other non-cellular structures. The purpose of the ECM is to provide a homeostatic environment for cells to reside in, and although the demands for cell homeostasis differ between tissues and organs, the major constituent of ECMs is collagen. Factors that may modulate collagen production include cancer, hypoxia, genetic disorders, inflammation, and aging.

The 28 known types of collagen comprise around 30% of total body protein content in animals. Despite the differences in their molecular assemblies, each type shares a characteristic protein motif: the collagen triple helix (Fig. 1).

Tropocollagen molecule showing the collagen triple helix and the three alpha chains that comprise the triple helix.
Figure 1: The collagen triple helix motif. Source: Protein Data Bank.

In order to study the physiological and pathological turnover of connective tissues and its components, Chondrex Inc. provides Collagen Detection ELISA Kits for quantifying various species of type I and type II collagen, as well as total collagen detection (see below), glycosaminoglycans (GAGs) detection, DNA Assay Kit, and metabolic quantification assays for tissue and cell culture samples.

Product Highlight: Total Collagen Detection Kits

Semi-Quantitative Assay: Sirius Red/Fast Green Collagen Staining Kit (Art. No. CHX-9046)

Sirius Red and Fast Green is a dye combination used to distinguish collagen from surrounding materials. Sirius Red specifically binds the [Gly-X-Y]n helical structure of fibrillar collagens, whereas Fast Green binds to non-collagenous proteins. As Sirius Red and Fast Green have absorptions at 540 nm and 605 nm respectively, the OD values of the extracted dyes can be used to calculate the collagen and non-collagenous protein content of samples. By exploiting the unique features of these two dyes, Chondrex, Inc. provides a simple semi-quantitative assay kit to determine the amounts of collagen and non-collagenous proteins in cultured cell layers and tissue sections.

Because this assay does not require collagen solubilization, it can be used to measure total collagen content in various tissues. The assay results can be normalized by results of non-collagenous proteins with Fast Green staining OD values. For general histological studies in which tissue sections are 10-20 μm thick, the assay sensitivity for collagen and non-collagenous proteins is greater than 3 μg/section and 50 μg/section, respectively. This kit contains enough reagents to stain 30-50 samples.

Quantitative Assay: Sirius Red Total Collagen Detection Kit (Art. No. CHX-9062)

Sirius Red Total Collagen Detection Kit utilizes Sirius red dye as a detection reagent to determine solubilized collagen concentration in samples. Sirius red is a unique dye which specifically binds to the [Gly-X-Y]n helical structure on fibrillar collagen (type I - V). This kit does not discriminate between collagen species and types and is therefore suitable for detecting total collagen content in samples. Due to the low level of collagen in cell culture media, additional concentration steps may be necessary if assaying cell culture media samples.
The Sirius Red Total Collagen Detection Kit will only detect solubilized native (undenatured) collagen from samples. If your study requires distinguishing between native and denatured collagen, the hydroxyproline assay can be used to detect total collagen. The difference between native (Sirius red assay) and total collagen (hydroxyproline assay) will equal denatured collagen levels. While the Sirius Red Total Collagen Detection Kit is designed to be used with a spectrophotometer, our Sirius Red Collagen Detection Plate Kit (Art. No. CHX-9062P) is designed for use with a 96-well ELISA plate. The plate kit is convenient for assaying various collagen-containing samples (tissue specimens, cell culture media, cultured cells) at one time. The total assay working time ranges from 30-60 minutes depending on the quantity of samples and is measured at an absorption of 540nm.