Abstract: A method of cleaving disulfide bonds is provided, which comprises: (a) introducing a liquid sample having disulfide bonds (e.g., proteins) into an electrochemical cell; and (b) subjecting the sample to a reducing potential to reduce the disulfide bonds, wherein the electrochemical cell comprises (i) a working electrode that contains titanium and (ii) an auxiliary electrode. An electrochemical flow cell for processing a sample fluid is also provided, which comprises: (a) a body comprising a flow path having inlet and an outlet; (b) a working electrode in fluid communication with the flow path; and (c) an auxiliary electrode; wherein the working electrode comprises at least 20 wt. % titanium in the form of elemental titanium, titanium-containing substances and/or titanium-containing alloys; and wherein the outlet is connected to an electrochemical detection (ECD) device, a NMR spectrometer or a mass spectrometer (MS) when the working electrode is a ruthenium-plated titanium electrode.

Abstract: An apparatus is disclosed comprising: a sample conduit; an electrochemical flow cell; a source of carrier fluid; a structure elucidation spectrometer; a conduit and an in-line sample reservoir, such that: (a) a first operating modus wherein the sample conduit is connected to the conduit via the electrochemical flow cell and the in-line sample reservoir, and the source of carrier fluid is connected to the by-passing the in-line sample reservoir, and (b) a second operating modus wherein the sample conduit is connected to the conduit by-passing the in-line sample reservoir, and the source of carrier fluid is connected to the structure elucidation spectrometer via the in-line sample reservoir. Decoupling of the electrochemical cell from the spectrometer allows for uncompromised selection of optimal electrochemical and separation conditions.

Abstract: A reconfigurable multi-mode post-column analysis system improves resolution of liquid chromatography detection data by providing a parking or MS/MS detection mode in which flow of column eluent is substantially reduced to provide greater analysis time within a single eluting detection peak. A micro switching valve unit is reconfigurable between normal (MS) mode that passes column eluent directly to an MS unit, and a peak parking (or MS/MS) mode, in which normal mode column flow is interrupted, and the gradient halted, while more slowly flowing the detection peak of interest through the MS unit. A micro syringe pump contributes to the substantially lower MS/MS flow rate. A MS control unit controls micro switching valve valves to reconfigure between MS and MS/MS modes. After a detection peak, MS mode is reestablished, and the system primary pump returns to normal mode flow rate and gradient conditions. Mode changes can be carried out for each chromatogram detection peak.

Abstract: A reconfigurable multi-mode post-column analysis system improves resolution of liquid chromatography detection data by providing a parking or MS/MS detection mode in which flow of column eluent is substantially reduced to provide greater analysis time within a single eluting detection peak. A micro switching valve unit is reconfigurable between normal (MS) mode that passes column eluent directly to an MS unit, and a peak parking (or MS/MS) mode, in which normal mode column flow is interrupted, and the gradient halted, while more slowly flowing the detection peak of interest through the MS unit. A micro syringe pump contributes to the substantially lower MS/MS flow rate. A MS control unit controls micro switching valve valves to reconfigure between MS and MS/MS modes. After a detection peak, MS mode is reestablished, and the system primary pump returns to normal mode flow rate and gradient conditions. Mode changes can be carried out for each chromatogram detection peak.

Abstract: A liquid chromatography micro-autosampler is disclosed that permits the sampling of very small samples quantities at high accuracy, while minimizing extracolumn band broadening. The autosampler employ a sample intake tubing connected to the injection valve, that is further connected to an aspirating device. The intake tubing terminates within the hollow bore of a needle which is used to penetrate sample containers. Improved injection profiles are obtained by minimizing injection plug dispersion with back flushing of the injection plug and a low dispersion injection routine and extremely small sample quantities can be handled with a micro pick-up injection routine.

Abstract: A method of analyzing fluid samples using a bent capillary flow cell, in which method an external UV/visible light ray beam is directed into an elongated section of the flow cell from a bend thereof, this incident light ray beam is limited to a solid acceptance angle .OMEGA.. This solid acceptance angle .OMEGA. is determined such that light rays which enter the elongated section traverse predominantly the longitudinal axis thereof, i.e. propagate through the fluid sample, providing an improved S/N ratio. Lens means, such as ball lenses, may be used at the entrance and exit side of the elongated section. A bent capillary flow cell is provided, in which the elongated section deviates by an angle .psi. from a line N perpendicular to a flat side face of a holding template.

Abstract: A capillary flow cell in which a capillary (9) partially extends along the optical path of the cell and has its two end portions (12, 13) bent to achieve an essentially Z-shaped configuration. A template (1) has a central bore (2) in which the middle part (11) of the capillary (9) is positioned. A method of manufacture of this capillary flow cell including inserting a capillary in a central bore of a template, heating the capillary immediately outside the bore to soften the capillary material, and bending the two ends to achieve an essentially Z-shaped or U-shaped configuration.

Abstract: A capillary flow cell in which a capillary (9) partially extends along the optical path of the cell and has its two end portions (12,13) bent to achieve an essentially Z-shaped configuration. A template (1) has a central bore (2) in which the middle part (11) of the capillary (9) is positioned. A method of manufacture of this capillary flow cell comprises the steps ofa) inserting a capillary in a central bore of a template,b) heating the capillary immediately outside the bore to soften the capillary materialc) bending the two ends to achieve an essentially Z-shaped or U-shaped configuration.