An increasing number of non-invasive medical applications utilize compounds enriched with the stable, non-radioactive isotope, Carbon-13 (¹³C). The metabolic probes consist of lipids, amino acids, carbohydrates, and non-pharmacological substances. These are used in clinical research to obtain critical information on in vivo enzyme activities, pharmocokinetics, and drug clearance. Typically, the labeled material is given orally and the key metabolic function is evaluated by measuring the increase of ¹³CO2 in the subject's exhaled breath at a specific time point or over a period of time. CIL is qualified as a cGMP manufacturer of pharmaceutical grade ¹³C Urea for use in the ¹³C Urea Breath Test for detection of Helicobacter pylori.