title: Pyridoxylated-polyhemoglobin solution: a low viscosity oxygen-delivering blood replacement fluid with normal oncotic pressure and long-term storage feasibility.
abstract: Stroma-free hemoglobin (P50 = 14 torr, T1/2 = 3 hr, COP = 60 torr @ 15 g%) was pyridoxylated (PP-SFHb P50 = 28 torr) and then cross-linked with glutaraldehyde to yield pyridoxylated-polyhemoglobin (PP-PolyHb). Sephadex G-200 gel chromatography showed 33% to be in the 470-750,000 dalton range, 60% 470,000 MW, and 10% remaining unmodified. PP-PolyHb (14 g%), was iso-oncotic (COP = 25 torr) with plasma, and had a viscosity at 37 degrees C = 3.8 cP. Despite glutaraldehyde crosslinking PP-PolyHb retained some cooperative oxygen binding (Hill coefficient n = 1.88), with a P50 of 20 torr. MetHb levels ranged from 3.1-4.8% in fresh PP-PolyHb solutions. Storage in liquid form was possible at 4 degrees C for up to 12 months, with MetHb forming at 0.6%/month. At 25 degrees C storage was possible for 6 months if lyophilized with 3.0% glucose, after which MetHb levels rose at 9.4%/year. At -20 degrees C, the lyophilized PP-PolyHb could be stored for up to 3 years, with MetHb levels remaining below 6.0%.
authors.affiliation: Artificial Cells & Organs Research Centre, Faculty of Medicine, McGill University, Montreal, Quebec, Canada.
authors.forename: P E
authors.initials: PE
authors.lastname: Keipert
authors.forename: T M
authors.initials: TM
authors.lastname: Chang
mesh_terms: D001802:Blood Substitutes; D003102:Colloids; D003432:Cross-Linking Reagents; D004355:Drug Stability; D005612:Freeze Drying; D006454:Hemoglobins / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006874:Hydrostatic Pressure; D008706:Methemoglobin / Q000032:analysis; D009994:Osmolar Concentration; D009997:Osmotic Pressure; D010100:Oxygen / Q000097:blood*; D011732:Pyridoxal Phosphate / Q000031:analogs & derivatives* / Q000378:metabolism; D012996:Solutions; D014783:Viscosity
chemical_list: D001802:Blood Substitutes; D003102:Colloids; D003432:Cross-Linking Reagents; D006454:Hemoglobins; D012996:Solutions; C030939:polyhemoglobin-pyridoxal-5-phosphate; D011732:Pyridoxal Phosphate; D008706:Methemoglobin; D010100:Oxygen