The NASDAQ stock exchange hammered another nail into Biopure Corp.‘s coffin, officially de-listing the Cambridge, Mass.-based blood substitue maker as it descends into Chapter 11 bankruptcy.

Biopure stock will no longer be offered on the exchange once trading opens August 7. Bids for the company’s assets are due a week later, ahead of an August 20 asset sale.

OPK Biotech LLC has already filed a $2.6 million “stalking horse” bid for virtually all of Biopure’s assets, including the patents for its flagship product, Hemopure, a blood-like fluid capable of carrying oxygen through the body.

The company listed a little more than $5 million in assets and about $2.7 million in liabilities at the time of its bankruptcy petition.