Physicochemical characteristics of OxyVita hemoglobin, a zero-linked polymer: liquid and powder preparations.
ABSTRACT OxyVita-zero-link polymerized hemoglobin (OxyVita Hb) is a novel generation hemoglobin based oxygen carrier (HBOC). Our focus in this paper is to address the question of "Why is OxyVita Hemoglobin different than the previous generation of HBOCs?" Several critical related topics will be discussed: 1) OxyVita's unique chemistry; 2) the introduction of a viable powder form of OxyVita hemoglobin for dissolution in IV water or other IV fluids; 3) the physiochemical characteristics of OxyVita hemoglobin preparations; 4) the ability to formulate different products based upon specific applications; and 5) the important storage properties essential for use in a wide range of geographical locations.
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ABSTRACT: OxyVita Hb is a new generation hemoglobin based oxygen carrier (HBOC) produced through modification of a zero-linked polymerization mechanism using activators which incorporate cross-linked bovine tetramer hemoglobin into "super-polymeric" macromolecules (Average molecular weight = 17 MDa) for the purpose of oxygen delivery when whole blood or packed red cells are not available. This molecular design approach was generated in order to address several fundamental biochemical and physiological weaknesses of previous generations of HBOCs. Observation during pre-clinical and clinical studies provided evidence that these early generation acellular HBOCs were directly associated with loss of retention within the circulatory system, extravasation across endothelial tissue membranes due to their small molecular size leading to arterial and venous vasoconstriction with coupled increases in mean arterial pressure (MAP). The inherent increase in molecular size and structural stability of the OxyVita Hb is a direct response to addressing these serious weaknesses that have occurred during the evolution of HBOC development within the past two decades. The nature of the zero-linked synthetic route eliminates any chemical linkers remaining in the product, eliminating side reaction concerns, such as reversibility and decomposition due to weak chemical bonds, dependency on temperature and pressure, and residual toxicity.Journal of functional biomaterials. 01/2011; 2(4):414-424.
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ABSTRACT: Hemoglobin-based oxygen carriers (HBOC) are being developed to provide the oxygen necessary in clinical situations when whole blood is not available. The safety and effectiveness of each HBOC must be determined before clinical approval. In the past several years animal studies have been conducted with zero-linked polymers to evaluate their effectiveness at delivering oxygen in vivo. Studies have addressed issues associated with interstitial extravasation, cerebral ischemia and blood flow, resuscitation, and coagulation interactions. Several of the investigations reviewed are based on early preparations of zero-linked polymerized bovine hemoglobins (ZL-HbBv), which contained a wide range of high-molecular-weight polymers. Recent studies using the Oxyvita product OxyVita Hb, which contains a more homogenous population (97%) of large-molecular-weight species (~17 MDa), are also included in this review.Journal of Artificial Organs 12/2010; 13(4):183-8. · 1.41 Impact Factor