The Sircol™ Collagen Assay is a dye-binding method for the analysis of acid and pepsin-soluble collagens. The Sircol Assay is suitable for monitoring collagen produced in situ or during in-vitro cell culture and in-vitro extracellular matrix, (ECM), formation:

in vivo

– collagen, soluble in cold acid or pepsin, recovered from mammalian soft tissues, cartilages and fluids.

in vitro

– collagen, soluble in cold acid or pepsin, released into cell culture medium during cell growth and cell maintenance.

– collagen, soluble in cold acid or pepsin, recovered from newly formed extracellular matrix that has been deposited onto cell culture treated plastic surfaces, (T-flasks and microwell plates).


Standard Assay Kit (110 assays) Product Code: S1000

Economy Pack (440 assays) Product Code: S5000

Sircol Dye Reagent (3 x 110ml) Product Code: S1005

Sircol Dye Release Reagent (3 x 150ml) Product Code: S1007

Sircol Bovine Collagen Reference Standard (0.5mg/ml, 3 x 5ml) Product Code: S1010

Sircol Rat Collagen Reference Standard (0.5mg/ml, 3 x 5ml) Product Code: S1011

Sircol Collagen Assay (110 assays) (Rat Collagen) Product Code: S1111

Sircol Dye & Dye Release Reagents (2 x 110ml + 2 x 150ml) Product Code: S1500


Manuals & Citations

The Sircol Soluble Assay Manual can be downloaded here.
Sircol Soluble Assay Manual

Scientific papers citing the use of the Sircol Soluble Assay in 2014 can be downloaded here.
Recent Sircol Assay Citations

Older citations of the use of the Sircol Soluble Assay can be downloaded here.
Older Sircol Assay Citations

Material Safety Data Sheet

The Sircol MSDS can be downloaded here.
Sircol MSDS


Sircol Collagen Assay

(a) Sets of collagen standards, Low range 0, 5, 10 & 15μg and High range 0, 15, 30 & 45μg, following collagen-dye mixing, centrifuging and removal of unbound dye, (duplicates not shown).
(b) Low Standards after adding 250μl Alkali Reagent.
High standards after adding 1000μl Alkali Reagent.
(c) Tube aliquots (200μl) transferred to 96 well microplate.

Frequently Asked Questions

Q. What is the sensitivity of the Sircol assay?

A. 1.0µg collagen. Quantities as low as 1.0µg of collagen can be recovered from a 1 ml volume if the Collagen Isolation & Concentration protocol is used (See Sircol assay manual for more detail).

Q. How long does the Sircol assay take to run?

A. 1.5 hours

Q. What forms of collagen does the Sircol assay measure?

A. Acid-soluble and pepsin-soluble collagens.

Q. What types of collagen can the Sircol assay be used with?

A. Mammalian collagens, Types I to V.

Q. What absorbance values can samples be measured at?

A. Absorbance spectrum maximum for Sircol dye in alkali reagent is 555 nm however absorbance settings within the range 520-570 nm will give suitable readings.

Q. How do I prepare samples for measurement with the Sircol assay?

A. Preparation details for cell culture and tissue samples can be found in the assay manual.

Sircol flow Chart

Sircol Flowchart

Customer Review

Katherine Yanhang Zhang, Associate Professor, Division of Materials Science
& Engineering, Boston University writes:

Aortic aneurysm is an important clinical condition characterized by common
structural changes such as the degradation of elastin. With the goal of
investigating the relationship between the mechanical behavior and the
structural/biochemical composition of an artery, the progressive changes
in mechanical properties of arteries under gradual elastin degradation were
studied. Elastin and collagen contents were measured using the Fastin
elastin and Sircol collagen assay kits
, respectively. Our results show
that gradual changes in the structure of elastin in the artery can lead to
a progression through different mechanical properties and reveal the
potential existence of an important transition stage that could contribute
to artery dilation during aneurysm formation.