Abstract: A novel process for selectively removing endotoxin from an aqueous solution containing bulk, iodinated, non-ionic contrast media and endotoxin by passing the solution through an activated carbon filter. The process can be economically practiced on a factory scale.

Abstract: Novel non-ionic contrast media are efficiently prepared from generally available ionic contrast media. Particularly, polyhydroxyhalohydrocarbons are employed with a triiodo-substituted acylamido benzoic acids in aqueous weakly basic media to selectively substitute the amido nitrogen, followed by activation of the carboxyl group for amide formation.

Abstract: Novel non-ionic contrast media of a hitherto unknown combination of low osmolality and low viscosity are efficiently prepared from generally available ionic contrast media or non-iodinated precursors. Particularly, polyhydroxyhalo-hydrocarbons are employed with a triiodo-substituted acylamido benzoic acids in aqueous weakly basic media to selectively substitute the amido nitrogen, followed by activation of the carboxyl group for amide formation.

Abstract: Methods and compositions are provided for producing sterile drug formulations, where drugs are thermolabile and pH sensitive. The method provides formulating the drug with a physiologically acceptable inorganic or organic acidic buffer for buffering at a pH in excess of 6, reducing the pH below about 5 by adding carbon dioxide, and heat sterilizing the formulation in a gas permeable sealed container. The resulting formulation is substantially free of degraded drug and at the desired physiologically acceptable pH. Also, formulations are provided which do not cause clotting during administration.