Hyaluronan defined

Scott, J.E. and Heatley, F., Biological properties of hyaluronan in aqueous solution are controlled and sequestered by reversible tertiary structures, defined by NMR spectroscopy, Biomacromolecules, 3, 547, 2002. 

The European Pharmacopoeia and HP standard viscosimetric method is described in Chapter IS. In the proposed method, both hyaluronidase and hyaluronan are available as well-defined stable standard preparations, eliminating variations in test results due to the absence of a well-defined substrate. With slight modifications the method can be used for the determination of hyaluronidase in serum [137]. 

This spectrophotometric method is based on the binding of a carbocyanine dye (1 -ethyl-2-[3-( 1 -ethyl-naphto[ 1,2rflthiazolin-2-ylidene)-2-methyl-propenyl]naphto [l,2rflthiazolium bromide, Stains all) to undegraded hyaluronan [34]. The unit of enzyme activity is defined as the amount of enzyme that will produce a 10% decrease in the absorbance of the dye-hyaluronan complex after one hour of incubation. 

Itano N, Kimata K. Mammalian hyaluronan synthases. lUBMB Life 2002 54 195-199. Jaakma U, Zhang BR, Larsson B, et al. Effects of sperm treatments on the in vitro development of bovine oocytes in semidefined and defined media. Theriogenology 1997 48 711-720. 

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