(Figure 1). The synthesis of CTT2-peptide enabled us to retain bioactivity that would otherwise not be present if CTT peptide itself was directly linked to lipids or PEG spacers. This is the first study, to our knowledge, that has utilized a peptide derived from a synthetic phage display library for constructing a more selective liposomal delivery system for targeting extracellular target molecules. Figure Inhibitors,research,lifescience,medical 1 Chemical structure of 125I-CTT2-peptide. CTT2-peptide is a 17-amino acid peptide with a disulphide bridge between the two cysteines. The amino terminal end of the peptide is amidated to increase its stability. Upon iodination, peptide labeling occurs … We initially present the synthesis of PEG-PE-CTT2 peptide-bound micelles and liposomes. The feasibility of utilizing micellar and liposomal nanoformulations Inhibitors,research,lifescience,medical as therapeutic delivery vehicles to achieve efficacy in ovarian carcinoma
models was explored by attaching the radioiodinated CTT peptide tracer, 125I-CTT2 peptide, to these platforms and loading them with doxorubicin, an inherently fluorescent chemotherapeutic agent. Biodistribution studies of both targeted nanoformulations were performed in normal and immunosuppressed subcutaneous human xenograft models using the CTT2-peptide. 2. Materials and Methods Tyrphostin AG-1478 purchase reagents — All reagents, unless stated otherwise, Inhibitors,research,lifescience,medical were obtained from Sigma-Aldrich (St Louis, Missouri, USA) and culture media from Gibco Life Technologies (Paisley, Scotland). PEG-PE-NHS was from Avanti Polar Lipids Inc. (Alabama, USA) as all the other lipids used in this study. 2.1. Synthesis of Peptides Peptides were synthesized on an Applied Biosystems 433A (Foster City, CA, USA) automatic synthesizer using Inhibitors,research,lifescience,medical Fmoc-chemistry. For disulfide generation, peptides were
dissolved at 1mg/ml in 0.05M ammonium acetate (pH 8) and mixed with H2O2 for 40min at room temperature so that 0.5ml of 3% H2O2 was added per 100mg peptide. The peptides were purified by reversed phase HPLC, and the molecular Inhibitors,research,lifescience,medical weight was identified by mass spectrometry analysis. 2.2. Synthesis of DSPE-PEG3400-CTT2 Coupling bioactive peptides to PEGylated lipids can alter the pharmacokinetics and dynamics of these peptides. For pharmaceutical formulation purposes, CTT2-peptide (Figure Histone demethylase 1) was covalently attached to the PEG phospholipid (Figure 2). Figure 2 Chemical structure of CTT2-PEG3400-DSPE. CTT2-PEG3400-DSPE was synthesized by coupling CTT2-peptide to PEG3400-DSPE, followed by purification of the reaction product from the initial mixture. In this procedure, the peptide called CTT2 (cyclo-GRENYHGCTTHWGFTLC-NH2) was covalently attached to PEG phospholipids through the chemical reaction between the terminal amine of the peptide and the functional NHS (hydroxysuccinimidyl) group at the end of the PEG phospholipid polymer chain.