E.i. Dupont De Nemours and Company

Baxter Travenol Laboratories, Inc.

Robert C Menson

Thomas H Adams

Venkatachalam Narayanswamy

James P Beck

Ronald Wayne Bussian

Richard C Burns

Walter Brent Aitken

An improved method and apparatus is disclosed for producing frozen particulate compositions from liquid feedstock. A continuous stream of liquid feedstock is passed through an orifice and into a liquid freezant without the orifice contacting the freezant. Compositions produced by this improved method have low proportions of fine and large particles, yielding particularly beneficial results in the case of quality control materials. The compositions are advantageously employed in automated weighing and filling apparatus.

Novel particulate compositions

Disclosed herein are a method and a reagent test kit, both using an improved substrate to measure the amylase content of a sample. The substrate used is a glycoside consisting of a defined polysaccharide glycosyl residue and a substituted aromatic radical attached to the terminal unit of the glycoside. When detached from the polysaccharide, the aglycone exhibits a different spectral absorbance than the substrate.

Amylase assay

Method and apparatus for making novel particulate compositions

Phosphoenol pyruvate carboxylase is stabilized to have a shelf life of six months or more by incorporating the phosphoenal pyruvate carboxylase in an aqueous solution containing from 0.002 to 0.05 molar sodium phosphate, from 1 to 10, and preferably 3 to 8, m molar aspartate, from 0.02 to 0.1 m molar ethylene diamine tetraacetic acid, from 0.6 to 3.15, and preferably 0.8 to 1.2, molar ammonium sulfate and up to 20 volume percent glycerol. The sodium phosphate acts as a buffer to maintain the pH of the solution at from 6.0 to 6.8.

Stabilization of phosphoenol pyruvate carboxylase

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Newport Beach, CA, United States of America

Robert C Menson