Hemoglobin is composed of one globin plus four hemes, heme consists of protoporphyrin IX and ferrous iron. The iron content of human hemoglobin is 0.338% (w/w) which gives a minimal molecular weight of 16,520, however, ultracentrifugal and osmotic pressure measurements indicate an actual molecular weight four times the minimum molecular weight. Appearance: Dark Brown-red powder Solubility (10mg/ml, H2O): Dark red brown Iron (Fe): 0.25-0.35% Water (Karl Fischer): 8% Storage and Stability: Lyophilized and reconstituted products are stable for 6 months after receipt at 4C. Reconstitute with sterile ddH2O. Do not freeze. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer. Note: Since native hemoglobin is readily oxidized in air, these preparations may be predominantly methemoglobin. Opened bottles should be capped tightly and kept in a dark, low humidity environment. Country of Origin: USA
