Dextran sorbitol

Fig. 19. Time-dependent development of structured flows in a dextran/sorbitol system (see legend of (Fig. 18) with blue-labelled dextran initially introduced into the bottom solution. The photograph was taken 2 h after formation of the boundary layer...

For approximately 80 raw materials the Ph. Eur. has set limits for endotoxin levels if they are intended for parenteral dosage forms. These include among others dextran, sorbitol and mannitol, sodium chloride, trometamol, water for injections. 

Lindvall and Anderson (90) prepared an ill-defined complex by adding an aqueous solution of ferric chloride in small increments to a solution containing sorbitol, citric acid, and the dextran held at 60°. The pH of the solution was adjusted to approximately 7.5 after the addition of each aliquot of the iron. The resulting iron complex can be precipitated with... 

Parenteral preparations Iron dextran (IMFERON) Iron-sorbitol citric acid complex (JECTOFER). 

Fig. 18. Transport of [3H]dextran over a boundary formed by layering 100 kg m 3 dextran T10 over a solution containing 100 kg m 3 dextran T10 (with [3H)dextran T10) and 50 kg m J sorbitol ( - ). The same system as above was used except that sorbitol was replaced by 5 kg m 3 dextran T10 ( - )...

Iron compounds for intramuscular administration are iron sorbitol-citric acid complex (iron sorbitex), iron dextran, iron glycerin-citric acid complex, and iron poljdso-maltose. The work on these formulations is largely old and has been reviewed in previous volumes in this series. 

Iron toxicity can be expected if the amount of free iron released into the plasma exceeds the plasma iron-binding capacity. This is more likely to occur when using iron sorbitol-citric acid complex (iron sorbitex), since the iron is less firmly bound than with iron dextran. Several conditions associated with low iron-binding capacity, such as malnutrition (kwashiorkor, malnutrition syndrome) and previous or simultaneous oral iron therapy appear to predispose to the development of these toxic reactions. In addition, folic acid deficiency has been reported to be a predisposing factor (SED-9, 516), the likely mechanism being altered iron utilization secondary to folic acid deficiency, which results in an increased saturation of ironbinding capacity. 

Hie stability of amoxicillin sodium salt in various intravenous infusion fluids has been studied [33-35], Degradation was faster at the higher amoxicillin concentrations [33] and particularly in fluids containing dextrose, dextran or sorbitol [33-35], Other studies also showed a deleterious effect of carbohydrates and alcohols on the stability of amoxicillin in solution [36,37],... 

Density materials used are practically identical with those used on the analytical scale, e.g., sucrose, and less frequently glycerol, sorbitol, ethylene glycol, ficoll and dextran. It should be noted that for the isoelectric fractionation of proteins with p7 values beyond 8.0 other density material than sucrose should be used (sucrose tends to be dissociated at high pH) (e.g., glycerol) (Fig. 6.29). 

Fig. 12. Time courses for benzylpenicillin open circles), benzylpenicilloyl ester solid dries), and benzylpenicilloic acid squares) in the reaction between benzylpenicillin (1.4 x 10 M) and sorbitol (a), glycerol (b), or dextran 40 (c) (all 10% W/V) at pH 9.25 (0.2 M carbonate) and 35 °C. (Bundgaard and Larsen 1978 b)...

Many compounds have been added to the disseminating fluid or powder to influence the subsequent infectivity of micro-organisms disseminated as an aerosol. Those found to afford protection include spent culture media, di-and tri-saccharides, raffinose, dextran, glucose and glycerol, polyhydric alcohols, sorbitol and inositol and sodium glutamate. 

Ferrous salts are absorbed more efficiently than ferric salts and are given in the treatment of iron-deficiency anaemia. They are not, however, always well tolerated and it is sometimes necessary to give special preparations, e.g. iron-dextran or iron-sorbitol parenterally. 

Bacteria found in the mouth have an enzyme that converts sucrose into a polysaccharide called dextran. Dextran is made up of glucose units joined mainly through a-1,3 - and a-1,6 -glycosidic linkages. About 10% of dental plaque is composed of dextran, and bacta-ia hidden in the plaque attack tooth enamel. This is the chemical basis for your dentist s warning not to eat candy. This is also why sorbitol and mannitol are the saccharides added to sugarless gum—they cannot be converted to dextran. 

Four chiral cryptands, derived form D-glucose, D-galactose, D-mannose, and L-tartaric add, have been prepared by short reaction sequences by application of a new, high pressure method. The cryoprotective effect of mannitol, sorbitol, glucose, maltoologosaccharides, and dextran on the denaturation of catalase during freeze-drying has been attributed to the replacement of lost water of hydration by monomolecular saccharide layers. ... 

Protein stability may be regarded as the opposite of denaturation. The stability of enzymes (and proteins) can be increased in many ways, e.g., by microenvironmental changes, immobilization, and protein engineering (78). Enzymes are more stable in the presence of polyols (ethylene glycol, glycerol, erythritol, and sorbitol), polymers (PEG, dextrans), and carbohydrates (sucrose, lactose, and trehalose). Hydrophilic enzymes are stabilized by the presence of salts (LiCl, NaCl, and KCl), whereas hydrophobic enzymes are hardly affected by salts. Proteins are also stabilized by compounds that bind specifically to the folded conformation. Most of the metalloenzymes and the enzymes that have an anion-binding site fall into this category. 

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