The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 30, 1986
Filed:
Oct. 23, 1985
Benjamin J Reichstein, Wilmette, IL (US);
University of Health Sciences/The Chicago Medical School, North Chicago, IL (US);
Abstract
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.