||Recombinant Human Long-R3-IGF-I produced inE. coliis a single, non-glycosylated, polypeptide chain containing 83 amino acids and having a molecular mass of 9.111 kDa.
||Human Long Arg3Insulin-like Growth Factor-I (Long-R3-IGF-I) is an 83 amino acid analog of human IGF-I comprising the complete human IGF-I sequence with the substitution of an Arg for the Glu at position 3 (hence R3), and a 13 amino acid extension peptide at the N-terminus. Scientists have engineered this analog with the express purpose of increasing biological activity. Human Long-R3-IGF-I is significantly more potent than human IGF-I in vitro. The enhanced potency is due to the markedly decreased binding of human Long-R3-IGF-I to IGF binding proteins which normally inhibit the biological actions of IGFs.
||>95% by SDS-PAGE and RP-HPLC.
||Lyophilized after extensive dialysis against acetic acid buffer.
||The ED50, calculated by the dose-dependant proliferation of murine BALB\C 3T3 cells is less than 1.0 ng/ml, corresponding to a specific activity of 1.0 x 106IU/mg. For most in-vitro applications, Long-R3-IGF-I exerts its biological activity in the concentration range of 0.2-20 ng/ml.
||Less than 0.1ng/µg (1IEU/µg) of Long-R3-IGF-I.
||It is recommended to reconstitute the lyophilized Long-R3-IGF-I in 500mM acetic acid not less than 100µg/ml, which can then be further diluted to other aqueous solutions.
||Lyophilized Long-R3-IGF-I although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution Long-R3-IGF-I should be stored at 4°C between 2-7 days and for future use below -18°C. For long-term storage it is recommended to add a carrier protein (0.1% HSA or BSA). Aliquot to avoid repeated freeze-thaw cycles.