Cellafluor is a fluorimetric reagent that can be used for the assay of cellulase (endo-1,4-β-glucanase). The reagent consists of 2 components:
2) β-glucosidase (Thermotoga maritima)
Upon incubation with a cellulase (endo-1,4-β-glucanase) enzyme, the functionalised trisaccharide is cleaved and the ancillary β-glucosidase can act to hydrolyse the fragment containing the 4-methylumbelliferyl group. The rate of formation of 4-methylumbelliferyl is directly proportional to the cellulase (endo-1,4-β-glucanase) activity. The assay reaction is terminated and full fluorescence obtained from the fluorophore by the addition of Tris buffer.