1240398-14-4

Leukotriene E₄-d₅ (LTE₄-d₅) is intended for use as an internal standard for the quantification of LTE₄ by GC- or LC-mass spectrometry. LTE₄ is produced by the action of dipeptidase on LTD₄, leaving only the cysteinyl group still attached to the fatty acid backbone. It is one of the constituents of slow-reacting substance of anaphylaxis (SRS-A). LTE₄ is considerably less active (8 to 12-fold) than LTC₄ in the biological activities characteristic of cysteinyl leukotrienes. Unlike LTC₄ and LTD₄, LTE₄ accumulates in both plasma and urine. Therefore, urinary excretion of LTE₄ is most often used as an indicator of asthma. In humans, basal levels of LTE₄ range from 1-100 pg/mg creatinine. In asthmatic patients, urinary LTE₄ levels increase to 80-1,000 pg/mg creatinine.

LTE₄-d₅ MaxSpec^® standard is a quantitative grade standard of LTE₄-d₅ (Item No. 10007858) that has been prepared specifically for mass spectrometry or any application where quantitative reproducibility is required. The solution has been prepared gravimetrically and is supplied in a deactivated glass ampule sealed under argon. The concentration was verified by comparison to an independently prepared calibration standard. This LTE₄-d₅ MaxSpec^® standard is guaranteed to meet identity, purity, stability, and concentration specifications and is provided with a batch-specific certificate of analysis. Ongoing stability testing is performed to ensure the concentration remains accurate throughout the shelf life of the product. Note: The amount of solution added to the vial is in excess of the listed amount. Therefore, it is necessary to accurately measure volumes for preparation of calibration standards. Follow recommended storage and handling conditions to maintain product quality.

Leukotriene E4-d5

Store at -80°C