Patent ID: 8088745

Claim:
A method for assaying α-L-iduronidase enzymatic activity, comprising: (a) incubating an α-L-iduronidase substrate which has the formula: Wherein m is an integer from 2 to 12, with α-L-iduronidase for a pre-determined time to provide a solution comprising an α-L-iduronidase product; (b) adding a buffer to the solution comprising the α-L-iduronidase product to quench the enzyme reaction; (c) adding an α-L-iduronidase internal standard to the solution comprising the α-L-iduronidase product to provide a solution comprising the α-L-iduronidase product and α-L-iduronidase internal standard; (d) extracting the solution comprising the α-L-iduronidase product and α-L-iduronidase internal standard with an organic solvent to provide an organic phase that includes the α-L-iduronidase product and α-L-iduronidase internal standard; and (e) determining the quantity of the α-L-iduronidase product.