Improved Preparation of Semisynthetic Phe^B1-Tritiated Insulin

Abstract

Semisynthetic [/V?e ß7 -3 H]insulin was prepared. Each intermediate in the synthesis was characterised by HPLC, polyacrylamide gel electrophoresis and end group determination by dansylation. The end product had a specific activity of up to 59 Ci/mmol. Semisynthetic insulin proved indistinguishable from natural insulin in its chemical and immunological properties and was shown to be biologically fully active by in vivo and in vitro assays. Verbesserte semisynthetische Präparation von Phe B1

The quantitation of biotinylated compounds by a solid‐phase assay using a 125I‐labelled biotin derivative

“…A small amount of [r4C]BNHS was included in the reaction to facilitate the identification of biotinylated insulin on the HPLC. The t-hoc groups were removed with anhydrous TFA and the product purified by HPLC using a O-70% gradient of acetonitrile in TFA as described before [8]. The degree of substitution of insulin with biotin was determined by the method of Swack et al [5] using streptavidin-Sepharose and [14C]biotin.…”