Abstract: A method for isolating urea and removing CO2 from plasma samples, comprising the following steps: a) providing a plasma sample; b) adding an acid so as to partially remove CO2; c) lyophilizing the sample so as to further remove CO2 and obtain a dried sample; and d) redissolving the dried sample and neutralizing to a pH value of 4 to 7 using a buffer solution, wherein optionally a filtration step is carried out before adding the acid.

Abstract: A method for isolating urea and removing CO2 from plasma samples, comprising the following steps: a) providing a plasma sample; b) adding an acid so as to partially remove CO2; c) lyophilizing the sample so as to further remove CO2 and obtain a dried sample; and d) redissolving the dried sample and neutralizing to a pH value of 4 to 7 using a buffer solution, wherein optionally a filtration step is carried out before adding the acid.

Abstract: Disclosed is a method for measuring pancreatic metabolism, which is characterized by the fact that the increase in 13CO2 in the exhaled breath is determined prior to and following the intravenous application of secretin as well as prior to and following the oral application of a 13C triglyceride.

Abstract: The method for the diagnosis of Helicobacter pylori infection by the oral administration of defined amounts of 13C-labeled urea and examination for 13C content of blood samples removed at a defined time is effected by a) removing from 0.1 to 0.6 ml of capillary blood from the finger or ear lobe of a patient or venous blood of a patient, in both cases with an empty stomach before the beginning of the test; b) administering an exact amount of from 10 to 50 mg of 13C-urea in aqueous solution with a pH value of 2 to 4 to the patient; c) again removing capillary or venous blood exactly after 10 to 15 min from the administration; and d) determining the 13C content of the blood samples by isotope ratio mass spectrometry (IRMS), and deducing the presence of Helicobacter pylori from the increase of the 13C values.

Abstract: The method for the diagnosis of Helicobacter pylori infection by the oral administration of defined amounts of 13C-labeled urea together with a sufficient amount of an acid bringing down the pH of the solution and thereafter examining the 13C content in the urea breast test (13C-UBT), is improved in that patients taking proton-pumping-inhibitors (PPIs) are administered higher amounts of acids, overcompensating for a time from 10 minutes to one hour the activity of the PPI. In one embodiment, therapy with PPI is discontinued for 1 to 3 days, which reduces the necessary amount of acid.

Abstract: The method for diagnosing lactose intolerance in patients by the oral administration of defined amounts of lactose, followed by assaying metabolites of lactose, is performed in a way where the lactose administered contains 99% 13-labeled lactose, preferably from 5 to 30 mg, and after the administration of the 13C-lactose, the content of 13C-labeled lactose is determined in a serum sample taken at a defined time after the administration. A diagnostic kit for performing the method consists of a capsule with from 5 to 30 mg of 99% 13C-labeled lactose, a patient instruction manual, a blood sampling device, sample containers for collecting the blood sample, and optionally a spatula and sample container for a stool specimen.

Abstract: The method for the diagnosis of Helicobacter pylori infection by the oral administration of defined amounts of 13C-labeled urea and examination for 13C content of blood samples removed at a defined time is effected by a) removing from 0.1 to 0.6 ml of capillary blood from the finger or ear lob of a patient or venous blood of a patient, in both cases with an empty stomach before the beginning of the test; b) administering an exact amount of from 10 to 50 mg of 13C-urea in aqueous solution with a pH value of 2 to 4 to the patient; c) again removing capillary or venous blood exactly after 10 to 15 min from the administration; and d) determining the 13C content of the blood samples by isotope ratio mass spectrometry (IRMS), and deducing the presence of Helicobacter pylori from the increase of the 13C values.

Abstract: The method for diagnosing lactose intolerance in patients by the oral administration of defined amounts of lactose, followed by assaying metabolites of lactose, is performed in a way where the lactose administered contains 99% 13C-labeled lactose, preferably from 5 to 30 mg, and after the administration of the lactose, the content of 13C-labeled lactose is determined in a serum sample taken at a defined time after the administration. A diagnostic kit for performing the method consists of a capsule with from 5 to 30 mg of 99% 13C-labeled lactose, a patient instruction manual, a blood sampling device, sample containers for collecting the blood sample, and optionally a spatula and sample container for a stool specimen.

Abstract: The method for the diagnosis of Helicobacter pylori infection by the oral administration of defined amounts of 13C-labeled urea and examination for 13C content of blood samples removed at a defined time is effected by a) removing from 0.1 to 0.6 ml of capillary blood from the finger or ear lob of a patient or venous blood of a patient, in both cases with an empty stomach before the beginning of the test; b) administering an exact amount of from 10 to 50 mg of 13C-urea in aqueous solution with a pH value of 2 to 4 to the patient; c) again removing capillary or venous blood exactly after 10 to 15 min from the administration; and d) determining the 13C content of the blood samples by isotope ratio mass spectrometry (IRMS), and deducing the presence of Helicobacter pylori from the increase of the 13C values.

Abstract: The method for determining the gastric emptying by orally administering a test substance and measuring its dwelling time in the stomach comprises determining the increase of 13CO2 in the exhaled respiratory air before and after the oral administration of free 13C-octanoic acid together with a standardized test meal.

Abstract: The method for diagnosing lactose intolerance in patients by the oral administration of defined amounts of lactose, followed by assaying metabolites of lactose, is performed in a way where the lactose administered contains 99% 13C-labeled lactose, preferably from 5 to 30 mg, and after the administration of the lactose, the, content of 13C-labeled lactose is determined in a serum sample taken at a defined time after the administration. A diagnostic kit for performing the method consists of a capsule with from 5 to 30 mg of 99% 13C-labeled lactose, a patient instruction manual, a blood sampling device, sample containers for collecting the blood sample, and optionally a spatula and sample container for a stool specimen.

Abstract: The method for the diagnosis of Helicobacter pylori infection by the oral administration of defined amounts of 13C-labeled urea and examination for 13C content of blood samples removed at a defined time is effected by