The polarographic determination of thyroxine and 3:5-diiodotyrosine.
نویسندگان
چکیده
Although biological methods are used for assessing the value of thyro-active materials, chemical methods are also available to determine the thyroxine content of such substances. These methods are mainly based on the estimation of iodine as 'thyroxine iodine' (Harington & Randall, 1929; Leland & Foster, 1932; Brand & Kassell, 1939). Polarographic analysis suggests itself as a means of simplifying this determination and this note records a preliminary study of the behaviour of thyroxine and diiodotyrosine at the dropping mercury cathode.
منابع مشابه
The determination of thyroxine in the thyroid gland of the rat.
Most procedures used for the separation of thyroxine from other iodinecontaining compounds of the thyroid gland are based on either the method of Harington and Randall (I) or that of Leland and Foster (2). In the former the thyroxine is separated from diiodotyrosine by precipitation in a slightly acid medium, whereas in Leland and Foster’s method thyroxine is extracted with butyl alcohol from a...
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Because of the similarity in structure between diiodotyrosine and thyroxine, Harington and Barger (1) suggested that the former is the precursor of thyroxine in the thyroid gland. The formation of thyroxine from diiodotyrosine has been demonstrated lately in vitro (2, 3). Recent data (4, 5) obtained with radioiodine used without carrier indicate the rates of incorporation of iodine into the var...
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 40 1 شماره
صفحات -
تاریخ انتشار 1946