Esophageal pH monitoring developed a dependable external reference electrode. Using this technique to monitor esophageal acid exposure patients for periods up to 24 hours, DeMeester and Johnson were able to identify the most important parameters of esophageal acid exposure, and they developed a composite pH score to quantify gastroesophageal reflux. The initial 24-hour pH studies required hospitalization until the introduction of microcircuits in the 1980s that allowed portable esophageal pH monitoring in an outpatient setting. Gastroesophageal reflux disease (GERD) is a common disease in western countries. In the United States, 7% of the population experiences heartburn daily and 44% at least once a
Gluconic acid Gluconic acid Gluconic acid is an organic compound with molecular formula CHO and condensed structural formula HOCH(CHOH)COOH. It is one of the 16 stereoisomers of 2,3,4,5,6-pentahydroxyhexanoic acid. In aqueous solution at neutral pH, gluconic acid forms the gluconate ion. The salts of gluconic acid are known as "gluconates". Gluconic acid, gluconate salts, and gluconate esters occur widely in nature because such species arise from the oxidation of glucose. Some drugs are injected in the form of gluconates. The chemical structure of gluconic acid consists of a six-carbon chain, with five hydroxyl groups positioned in the same way as in the