A liquid delivery device includes at least one liquid delivery pump that delivers liquid, at least one main channel communicating with an outlet of the liquid delivery pump, at least one branch channel branched from the main channel, and a switching valve that has, as a port for connecting channels, at least a port to which the main channel is connected, a port to which the branch channel is connected, at least one output port for outputting liquid delivered by the liquid delivery pump through the main channel, and at least one drain port leading to a drain, and is configured to be selectively switched to a first state, in which the main channel is connected to the output port while the branch channel is not connected to any channel, and a second state in which the branch channel is connected to the drain port while the main channel is not connected to any channel.

A liquid delivery device includes at least one liquid delivery pump that delivers liquid, at least one main channel communicating with an outlet of the liquid delivery pump, at least one branch channel branched from the main channel, and a switching valve that has, as a port for connecting channels, at least a port to which the main channel is connected, a port to which the branch channel is connected, at least one output port for outputting liquid delivered by the liquid delivery pump through the main channel, and at least one drain port leading to a drain, and is configured to be selectively switched to a first state, in which the main channel is connected to the output port while the branch channel is not connected to any channel, and a second state in which the branch channel is connected to the drain port while the main channel is not connected to any channel.

The disclosure relates to a system for liquid sample introduction into a chromatography system. The system includes a syringe, a first valve in fluid communication with the syringe, a second valve in fluid communication with the sample, a vessel located between, and in fluid communication with, the first and second valves, a third valve in fluid communication with the first valve, the second valve and a chromatography column, and a pump in fluid communication with the third valve and a mobile phase. When the valves are in a first position the syringe draws the sample into the vessel. The mobile phase flows to the chromatography column. When the valves are in a second position, a portion of the mobile phase flows into the vessel, mixing with and pressurizing the sample. When the valves are in a third position, the mixed and pressurized sample flows to the chromatography column.

A continuous flow mixer for use in a chromatography system includes a first channel structure located between a mixer inlet and a mixer outlet. The first channel structure includes a first inlet branch, a second inlet branch, a plurality of outlet branches including at least a first outlet branch and a second outlet branch, a first plurality of branches splitting from the first inlet branch, each branch of the first plurality of branches connected to a different of the plurality of outlet branches, and a second plurality of branches splitting from the second inlet branch, each branch of the second plurality of branches connected to a different of the plurality of outlet branches. At least two branches of the first and second plurality of branches that are connected to the first outlet branch are offset in fluid residence time through the at least two branches.

In the present system and method, a conduit from a LC device continuously transports solvent, buffers, and analytes to the inlet of a solvent removal and analyte conversion device which evaporates the solvents, leaving non-volatile analytes for detection. The device comprises a rotating disk. The liquid chromatograph device can be any device using liquid chromatography to separate molecules. The solvents in the LC effluent can include, but are not limited to, water, methanol, acetonitrile, tetrahydrofuran, and acetone. After removal of the volatile components, the non-volatile analytes are converted with a concentrated energy source so that they may be detectable.

A chromatography system includes a gradient delay volume defined as an overall fluid volume between where gradient is proportioned until an inlet of a chromatography column, a pump pumping a flow of gradient; and at least one valve located downstream from the pump, the at least one valve having a plurality of ports including an inlet port that receives the flow of gradient from the pump and an outlet port through which the flow of gradient exits the at least one valve, the at least one valve having at least two positions. A first position of the at least two positions of the at least one valve increases the gradient delay volume of the chromatography system relative to when the at least one valve is in a second position.

The liquid delivery device includes a liquid delivery controller configured to operate, in a complementary manner, a primary plunger pump and a secondary plunger pump of each of a first liquid delivery pump and a second liquid delivery pump so that the first liquid delivery pump and the second liquid delivery pump perform continuous liquid delivery at a preset flow rate to each other, and a forcible synchronization part configured to forcibly synchronize operation states of the secondary plunger pumps of the first liquid delivery pump and the second liquid delivery pump by operating the primary plunger pump and the secondary plunger pump of the first liquid delivery pump and the second liquid delivery pump at the calculated operation speed.

When a flow path switch valve is in a first flow path state, an aqueous solvent supplied by an aqueous solvent supplier is guided to a first flow path, and a pH of the aqueous solvent is measured by a pH meter provided in the first flow path. When the flow path switch valve is in a second flow path state, the aqueous solvent supplied by the aqueous solvent supplier is guided to a second flow path. A sample to be analyzed is supplied by a sample supplier at a position farther downstream than the flow path switch valve. The solvent that has passed through the second flow path and the sample supplied by the sample supplier are guided to a separation column. The sample that has passed through the separation column is detected by a detector.

A method for injecting a diluted sample in a chromatography system includes merging a flow of a sample and a flow of a diluent to form a flow of a diluted sample. A dilution ratio of the diluted sample equals a sum of the volumetric flow rates of the sample and the diluent divided by the volumetric flow rate of the sample. The diluted sample is stored in a holding element before injection into a chromatographic system flow. Sample dilution occurs under low pressure relative to the chromatographic flow thereby allowing lower pressure sample and diluent syringes to be used. Other benefits include reduced compressibility and a reduction in leaks due to the lower pressure operation. The method avoids problems associated with manual techniques which can introduce errors due, for example, to loss of sample, sample precipitation and adsorption of sample to vials.

Provided that elapsed time from the start of the flow-in of an eluent into a column is t0 and the mobility R.sub.f.sup.c(t/t0) of a component c in a sample is represented by a function of elapsed time t from the start of the flow-in of a sample into the column, elution time t.sub.r.sup.c from the flow-in of the sample into the column to the flow-out of the component c from the column is calculated by using Equation (1). In doing so, the mobility R.sub.f.sup.c(t/t0) in Equation (1) is represented by Equation (2). $\begin{array}{cc}{\int }_0^{t_r^c}{R}_f^c\left(\frac{t}{t_0}\right)d\left(\frac{t}{t_0}\right)=1& \left(1\right)\\ R_f^c\left(\frac{t}{t_0}\right)=1-{}^{}\end{array}$