Instrumentation. The facility possesses three Protein Technology automatic peptide synthesizers and one Advanced ChemTech (ACT 90) peptide synthesizer. While the Protein Technology peptide synthesizers can provide small amounts of the peptides (in mg quantities) in a shorter duration due to the addition of ten times excess of incoming amino acids on to the amino acid-resin, the ACT can provide 10g quantities of peptides but the process is slow since one amino acid is added per day after the completion of reaction is ascertained at each stage of the synthesis. Since the starting resin used in ACT 90 is more, we avoid adding more than the required excess of amino acid derivatives at each stage in order to save costs on amino acid derivatives. For the purification of peptides the core facility possesses three Beckman analytical HPLC and two preparative HPLC units (Beckman and Varian). In addition to this, the core facility utilizes BioRad FPLC systems that are connected to Michel Muller Medium Pressure Liquid Chromatography (MPLC) glass columns. These columns are of various sizes with the smallest (analytical) containing 12g of the stationary phase (C-4 or C-18 silica gel) and the biggest column containing 800g of """"""""home made"""""""" reverse phase stationary phase (C-4 and C-18 Reversed Phase silica gels). We routinely alkylate Silica Gel with various chain-lengths of fatty acids. At a time we produce 2 kg to 4kg of the stationary phase for home made columns. This provides a higher capacity to purify large quantities of synthetic peptides. These columns are also used to purify recombinant proteins. A typical procedure will be described in the Methods Section.
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