Thrombin, a serine protease, plays a central role in hemostasis by converting soluble plasma fibrinogen into an insoluble fibrin clot and by promoting platelet aggregation.¹ Thrombin also influences a number of normal and pathological processes, including inflammation,² tissue repair,³ embryogenesis,⁴ angiogenesis,⁵ and tumor invasion.⁶

AnaSpec is pleased to introduce the industry’s first FRET based thrombin assay – the SensoLyte^® 520 Thrombin Activity Assay Kit. This kit employs a novel internally quenched 5-FAM/QXL^® 520 FRET substrate (Figure 1). Thrombin cleaves the FRET substrate into two separate fragments resulting in release of the fluorescence of 5-FAM, a green dye. Increase of fluorescence can be monitored at the commonly used excitation and emission wavelengths of 490 nm and 520 nm, respectively. The long wavelength fluorescence of 5-FAM is less interfered by the autofluorescence of components in biological samples and test compounds, resulting in a high signal to background ratio. Figure 2 shows the inhibition data.

	Figure 1. Proteolytic cleavage of the 5-FAM/QXL® 520 FRET peptide by thrombin increases the distance between the donor and quencher. This results in the release of 5-FAM fluorescence.
	Figure 2. Inhibition of thrombin activity was determined using the SensoLyte® 520 Thrombin Assay Kit.

AnaSpec also offers a shorter wavelength thrombin assay, which employs an AFC (7-amido-4-trifluoromethylcoumarin) labeled substrate, the SensoLyte^® AFC Thrombin Activity Assay Kit.

Related Products :

Plasmin Assay Kits
RGD Peptides
Fibrinogen and Related Peptides
Fibronectin Fragments

References

1. Crawley, JT. et al. J. Thromb. Hemost. 5, 95(2007).
2. Croce, K. et al. Curr. Opin. Hematol. 14, 55 (2007).
3. Artuc, M. et al. Exp. Dermatol. 15, 523 (2006).
4. Griffin, CT. et al. Science 293, 1666 (2001).
5. Maragoudakis, ME. et al. Biochem. Soc. Trans. 30, 173 (2002).
6. Snyder, KM. et al. Semin. Thromb. Hemost. 34, 734 (2008).