04632119 is referenced by 55 patents and cites 8 patents.

A unique ingestible and retrievable ambulatory esophageal monitor for colorimetric analysis of ambient pH within selected portions of the esophagus comprising a nasoesophgeal conduit at least one generally transparent semi-permeable envelope carried proximal the distal end of the conduit for positioning within the distal esophagus. The envelope contains an ion exchange color indicator composition comprised of a weak cation exchange substance selected from the group comprising a resin, a cellulose or an agarose and intermixed and bound therein being an indicator dye preferably either methylene blue or azure A. The ion exchange substance having a disassociation potential (pK) of at least 4 so that the indicator dye selectively disassociates causing the envelope to visually discolorize when exposed to a clinically significant ambient pH of 4 or less within the esophagus.

Title
Ambulatory esophageal pH monitor
Application Number
6/790359
Publication Number
4632119
Application Date
October 23, 1985
Publication Date
December 30, 1986
Inventor
Benjamin J Reichstein
Wilmette
IL, US
Agent
Wallenstein Wagner Hattis Strampel & Aubel
Assignee
University of Health Sciences The Chicago Medical School
IL, US
IPC
A61B 5/00
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