Thyroid hormones Thyroxine (T4) and 3,3’,5-triidothyronine (T3) are regulators of metabolism, growth, and development. The levels of T3 and T4 are useful biomarkers of overall thyroid function. Hyperthyroidism or hypothyroidism can result from autoimmune disorders, such as Graves’ disease, certain medications, thyroid cancer, and can often occur during pregnancy. Individuals suffering from thyroid dysfunction suffer from a broad range of symptoms including weakness and fatigue. The Tasso-M20 device enables at-home, automated, self-collection of the sample. The device automatically collects four 17.5 microliter samples. The accurate quantitation of these hormones extracted from the Tasso-M20 device and analyzed using HPLC-MS/MS was performed in this study. The dynamic range is 0.100-500 ng/mL and is adequate to simultaneously detect T3 and T4 from samples.