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LC/MS Analysis of Thyroid Hormones on Ascentis® Express F5

LC/MS Analysis of Thyroid Hormones on Ascentis® Express F5

Conditions

column Ascentis Express F5, 5.0 cm x 3.0 mm I.D., 2.7 µm particles (53576-U)
column temp. 45 C
mobile phase [A] 100 mM ammonium acetate, pH 4.0 with acidic acid: water (10:90); [B] 100 mM ammonium acetate, pH with acidic acid: acetonitrile (10:90)
gradient 15 to 55% B in 3 min; to 100% B in 0.1 min; held at 100% B for 1 min; to 15% B in 0.2 min; held at 15% B for 1.7 min
flow rate 0.5 ml/min
pressure 1455 psi (100 bar)
sample 100 ng/mL in 99:1 water:acetonitrile
injection 4 µl
detector MS, ESI (+) TOF, SIM, (T3 and rT3 m/z 651.8000; T4 m/z 777.7000

Description

Analysis Note The thyroid hormones, triiodothyronine (T3) and its prohormone, thyroxine (T4), are tyrosine-based hormones produced by the thyroid gland that are primarily responsible for regulation of metabolism. Thyroxine, or T4, is the thyroid “storage hormone.” Triodothyronine, or T3, is the “energy hormone.” For the body to use T4, it must first convert it to the active hormone T3, giving energy to every cell in the body. Another critical thyroid hormone is reverse T3 (rT3). Reverse T3 is the body’s “emergency brake.” rT3 is a metabolite of T4 (thyroxine). Typically, when T4 loses an atom of iodine -- a process known as monodeiodination, or T4 to T3 conversion -- it becomes triiodothyronine (T3), the active thyroid hormone. But in some cases, the body conserves energy by converting the T4 instead into rT3, an inactive form of T3 that is incapable of delivering oxygen and energy to the cells, as T3 does. The Ascentis Express F5 shows baseline resolution of these three common thyroid hormones in a 6 minute gradient.
Categories Analytical Chromatography, Hormones
Featured Industry Life Science and Biopharma
Legal Information Ascentis is a registered trademark of Sigma-Aldrich Co. LLC
suitability application for LC-MS

Materials

     
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