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X-Ray Crystallography ReagentMicrocapsules prepared by encapsulating an aqueous solution of a protein, drug or other bioactive substance inside a semi-permeable membrane by are disclosed. The microcapsules are formed by interfacial coacervation under conditions where the shear forces are limited to 0-100 dynes per square centimeter at the interface. By placing the microcapsules in a high osmotic dewatering solution. the protein solution is gradually made saturated and then supersaturated. and the controlled nucleation and crystallization of the protein is achieved. The crystal-filled microcapsules prepared by this method can be conveniently harvested and stored while keeping the encapsulated crystals in essentially pristine condition due to the rugged. protective membrane. Because the membrane components themselves are x-ray transparent, large crystal-containing microcapsules can be individually selected, mounted in x-ray capillary tubes and subjected to high energy x-ray diffraction studies to determine the 3-D smucture of the protein molecules. Certain embodiments of the microcapsules of the invention have composite polymeric outer membranes which are somewhat elastic, water insoluble, permeable only to water, salts, and low molecular weight molecules and are structurally stable in fluid shear forces typically encountered in the human vascular system.
Document ID
20040000691
Acquisition Source
Headquarters
Document Type
Other - Patent
Authors
Dennis R Morrison
Benjamin Mosier
Date Acquired
August 21, 2013
Publication Date
January 7, 2004
Subject Category
Solid-State Physics
Report/Patent Number
NASA-Case-MSC-22936-4
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-Patent-6,599,449
Patent Application
US-Patent-Appl-SN-774169
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