available in multiple molecular weights ranging from 3 kDa to 2 MDa. The larger dextrans (>60,000 Da) are excreted poorly from the kidney, so remain in the blood for as long as weeks until they are metabolized. Consequently, they have prolonged antithrombotic and colloidal effects. In this family, dextran-40 (MW: 40,000 Da), has been the most popular member for anticoagulation therapy. Close to 70% of dextran-40 is excreted in urine within the first 24 hours after intravenous infusion, while the remaining 30% are retained for several more days. Other medical uses Dextran is used in some eye drops as a lubricant. and in certain intravenous fluids to solubilize other factors, such as iron (in a solution known as Iron Dextran). Intravenous solutions with dextran function both as volume expanders and means of parenteral nutrition. Such a solution provides an osmotically neutral fluid that once in the body is digested by cells into glucose and free water. It is occasionally used to replace lost blood in emergency situations, when replacement blood is not available, but must be used with caution as it does not provide necessary electrolytes and can cause hyponatremia or other electrolyte disturbances. Dextran also increases blood sugar levels. Dextran can be used in an ATPS for PEGylation Laboratory uses Dextran is used in the osmotic stress technique for applying osmotic pressure to biological molecules. It is also used in some size-exclusion chromatography matrices; an example is Sephadex. Dextran has also been used in bead form to aid in bioreactor applications. Dextran has been used as an immobilization agent in biosensors. Dextran preferentially binds to early endosomes; fluorescent-labelled dextran can be used to visualize these endosomes under a microscope. Dextran can be used as a stabilizing coating to protect metal nanoparticles from oxidation and improve biocompatibility. Dextran coupled with a fluorescent molecule such as fluorescein isothiocyanate can be used to create concentration gradients of diffusible molecules for imaging and allow subsequent characterization of gradient slope. Solutions of fluorescently-labelled dextran can be perfused through engineered vessels to analyze vascular permeability Dextran is used to make microcarriers for industrial cell culture Orally-administered dextran sodium sulphate is used to induce colitis in animal models of inflammatory bowel disease. Side effects Although relatively few side effects are associated with dextran use, these side effects can be very serious. These include anaphylaxis, volume overload, pulmonary edema, cerebral edema, or platelet dysfunction. An uncommon but