Studies of properties and potential applications of some soluble salts of cellulose acetate phthalate. Part 1: rheological behavior and aging effect.

Rheological behaviour for solutions of the sodium, ammonium, and triethanolamie salts of cellulose acetate phthalate was studied. The comparative resistance to microbial growth and to changes in pH values exhibited by these solutions on storage was also investigated. The results indicated that the viscosities of these solutions were temperature and concentration dependent and that increasing the rate of shear produced only a slight increase of viscosity. Solutions of ammonium and the triethanolamine salts did not support any apparent microbial growth during storage at room temperature of three weeks, but the sodium salt appeared to suffer from microbial contamination. However, the use of a mixture of 0.15% methylparaben and 0.05% propylparaben prevented such contamination. The pH values of all the slat solutions studied appeared to decrease on storage.

O-phthalaldehyde: fluorogenic detection of primary amines in the picomole range. Comparison with fluorescamine and ninhydrin.

O-Phthalaldehyde, in the presence of 2-mercaptoethanol, reacts with primary amines to form highly fluorescent products. Picomole quantities of amino acids, peptides, and proteins can be detected easily. o-Phthalaldehyde is five to ten times more sensitive than fluorescamine and is soluble and stable in aqueous buffers.

Blood components in the treatment of acute blood loss: use of freeze-preserved red cells, platelets, and plasma proteins.

To avoid untoward reactions from blood transfusions and to make best use of the limited supply of blood, anesthesiologists and surgeons have many newly developed means at their disposal. Blood components should be separated from whole blood at the time of collection and prepared for either liquid or freeze-preservation. Citrate-phosphate-dextrose (CPD) blood should be separated into its components at room temperature within 4 hours of collection for greatest service from each collected unit. Red cell concentrates with hematocrits of 70 volumes percent can be prepared from the whole blood at the time of collection and frozen either shortly thereafter or after storage at 4 degrees C. for up to 3 weeks. Red-cell levels of 2, 3-diphosphoglycerate (2, 3-DPG) and adenosine triphosphate (ATP) can be increased by a rejuvenation process prior to freeze-preservation with either 40 percent W/V glycerol and storage at minus 80 degrees C. or with 20 percent W/V glycerol and storage at minus 150 degrees C. While hemorrhagic shock can best be managed with fresh whole blood, such blood is often not available; liquid- and freeze-preserved products serve as best substitutes. When previously-frozen washed red cells are used, crystalloid, colloid, coagulation factors, and platelets may also be required. Platelet concentrates stored at 4 degrees C. provide platelets that are hemostatically effective immediately upon infusion but have poor circulation. Platelet concentrates stored at 22 degrees C. provide platelets that have good circulation but upon transfusion have impaired hemostatic effectiveness. The coagulation factors and oncotic properties of plasma protein necessary for proper treatment of patients in hemorrhagic shock can be met by an adequate supply of fresh-frozen plasma and albumin. When liquid-stored red-cell concentrates or whole blood is given, filters must be used to remove the accumulated amorphous material, although the actual effects of the infused microaggregates are not yet known.

High-pressure liquid chromatographic determination of chlorpropamide in tablet formulations.

A method was developed for the quantitative determination of chlorpropamide in tablet formulations by high-pressure liquid chromatography after homogenization of the sample with methanol.