Versatile high-performance liquid chromatographic computer system for solvent delivery, gradient control and data acquisition using the Commodore 64 personal computer

An interface for a high-performance liquid chromatographic system based on the Commodore 64 personal computer has been designed as an alternative to the expensive and somewhat inflexible solvent programmers and data acquisition systems offered by commercial manufacturers. The system consists of the Commodore 64 with a single disk drive and monitor, and an interface that directly controls the flow-rates of two Waters pumps for solvent delivery in either isocratic or gradient mode, as well as analog-to-digital conversion of chromatographic data and either graphic data output to a dot-matrix printer or digital-to-analog conversion for output to a chart recorder. The interface permits computer-controlled flow-rates of up to 10.0 ml/min, with an accuracy of 0.0047 ml/min at flow-rates of 4.1 ml/min and an accuracy of 0.03 ml/min at flow-rates of 10 ml/min. The software for data analysis permits tabulation of elution times and areas for the peaks in a chromatogram with an option for baseline correction. The data are stored on floppy disks together with information pertinent to the chromatogram (flow-rate, solvent composition, etc.).     

Nanoimaging with a compact extreme-ultraviolet laser

Images with a spatial resolution of 120-150 nm were obtained with 46.9 nm light from a compact capillary-discharge laser by use of the combination of a Sc-Si multilayer-coated Schwarzschild condenser and a free-standing imaging zone plate. The results are relevant to the development of compact extreme-ultraviolet laser-based imaging tools for nanoscience and nanotechnology.     

Erratum to: Determination of metal ion content of beverages and estimation of target hazard quotients: a comparative study

This is a correction to the following paper: Hague T, Petroczi A, Andrews PR, Barker J, Naughton DP: Determination of metal ion content of beverages and estimation of target hazard quotients: a comparative study. Chem Central J 2008, 2:13.     

Interaction between glycophorin and phospholipids in recombined systems.

Both the MN-glycoprotein from human erythrocytes and the hydrophobic fragment from the protein isolated with trypsin treatment, T(is), have been recombined with egg phosphatidylcholine in bilayers at various phospholipid/protein ratios. In order to investigate the effect of the protein on the phospholipid headgroups, 31P nuclear magnetic resonance spectra were obtained with the MN-glycoprotein recombined with egg phosphatidylcholine, which revealed two classes of phospholipid environments, one immobilized and one not immobilized. Electron spin resonance (ESR) of fatty acid methyl ester spin labels provided supporting evidence. Computer analysis of the ESR spectra indicate that 4-5 moles of phospholipid are immobilized per mole of protein over a wide range of lipid-to-protein ratios. The immobilization of the phospholipids appears mediated by both the polar headgroups and the hydrocarbon tails of the phospholipid.