Abstract: A target structure is provided for use in a magnetically enhanced diode sputter coating source having a sputtering target which at end-of-life has an eroded surface with a known shape. The sputtering target has a non-sputtered profiled back surface conforming substantially in shape to the eroded surface at end-of-life. A backing plate is bonded to the sputtering target which has a bonding surface complementary to the non-sputtered back surface of the sputtering target and is designed to mate therewith. A method is provided for fabricating the target structure and bonding the sputtering target to the backing plate by isostatic pressing.
Abstract: Disclosed is a method for enhancing the cleavage of an acyl thiohydantoin bond, for example, for use in C-terminal peptide sequencing. An acyl thiohydantoin is alkylated to form an adduct on the thiohydantoin, and the adduct-containing thiohydantoin is cleaved at its acyl bond by reaction with a cleaving agent under substantially anhydrous, acidic conditions. In C-terminal amino acid sequencing, the cleaved product is analyzed to identify the C-terminal amino acid.
Abstract: A method for achieving desired electroosmotic flow characteristics in a capillary tube having charged surface groups. An electrolyte solution containing a compound effective to stably alter the charge of the tube walls is drawn into and through the tube during while the electroosmotic flow rate in the tube is being monitored, until a desired electroosmotic flow rate is achieved. The method can be used to optimize electrophoretic separation of charged protein or nucleic acid species in a capillary tube, and to produce capillary tubes with desired charge density properties.
Abstract: A supported, substantially uniform matrix for use in electric field-induced separation of molecular components in a sample. The matrix is prepared by forming a viscoelastic polymer matrix and pumping the matrix into a capillary or preparative-scale tube. The polymer type, concentration, and molecular weight are selected to optimize separation of protein or nucleic acid components. The matrix can be expelled from the tube, after fractionation, for analysis and/or recovery of fractionated components.
Abstract: A method of C-terminal peptide sequencing. The peptide is reacted with an activated support derivatized with a mixed anhydride of isothiocyanic acid and carboxylic or carbonic acid, under basic conditions. The peptidyl thiohydantoin which forms is separated from the solid support and further reacted with a cleaving agent carried on a second solid support, to release a free C-terminal amino acyl thiohydantoin from the peptide. The free thiohydantoin is analyzed to determine the C-terminal peptide residue. The residual peptide can be recycled through the supports for successive C-terminal residue determinations.