A fluid processing apparatus includes a first fluid separation apparatus including a first fluid pump, configured for driving a first mobile phase, and a first separation unit configured for separating a fluidic sample when within the first mobile phase. A sampling unit includes a modulation buffering unit and a modulation drive, wherein the modulation drive is configured for introducing fluid into the modulation buffering unit. A switching unit is configured, in a first switching state, for introducing fluid into the modulation buffering unit from downstream of the first separation unit, and, in a second switching state, for introducing fluid buffered in the modulation buffering unit in a first flow path between the first fluid pump and the first separation unit.

A fluid modulator includes a fluid manifold, fluid valve, and pressure/flow controller. The manifold may include a primary tee, exhaust tee, secondary tee, loop conduit, and joining tube. The valve may include a common port, normally-open output port connected to the secondary tee, and normally-closed output port connected to the primary tee. The controller may be configured to provide auxiliary fluid to the common port. In embodiments, the primary tee, exhaust tee, and secondary tee are configured with the primary tee and secondary tee situated at ends of the fluid manifold and the exhaust tee disposed therebetween. In other embodiments, the exhaust tee, the primary tee, and the secondary tee are distributed in a linear fashion with the exhaust tee and secondary tee situated at ends of the fluid manifold and the primary tee disposed therebetween. An embodiment with a single, unitary 5-port fluid manifold is also disclosed.

A multi-dimensional liquid analysis system includes a flow splitter for separating mobile phase outflow from a first dimension liquid analysis system into first and second liquid split outlet flows. Volumetric flow rate control of the split outlet flows is provided by a flow control pump which withdraws one of the split outlet flows from the flow splitter at a controlled withdrawal flow rate to define the other split outlet flow rate as the difference between the outflow rate from the first dimension system and the withdrawal flow rate. In this manner, accurate and consistent flow division can be accomplished, which is particularly useful for multi-dimensional liquid analysis.

Methods for classification of hydrocarbon mixtures that include performing two-dimensional gas chromatography on a hydrocarbon mixture to obtain a chromatogram using a two-dimensional gas chromatograph equipped with a flame ionization detector, a reversed phase column configuration with a primary mid-polar or polar column and a secondary non-polar column, and a standard mixture. Classification is performed in which groups of hydrocarbons are identified and labeled based on peaks associated with the standard mixture, after which a quantification process is performed.

A re-sampling device for two-dimensional gas chromatography includes a modulator and at least one of a first splitter disposed upstream from the modulator and configured to split an effluent from a primary column and deliver a portion of the effluent to waste and a portion of the effluent to the modulator, or a second splitter disposed downstream from the modulator and configured to split the effluent to deliver a portion of the effluent to waste and a portion of the effluent to a secondary column.

A method for applying a heating sequence for a modulator includes, during a first period of time, heating a first heating zone disposed along a length of the modulator without heating a second heating zone to cause a sample trapped from a first transfer line at an entrance of the modulator to move from the first heating zone to the second heating zone. The method also includes, during a second time period, withdrawing the heating of the first heating zone to prevent the sample from entering the modulator from the first transfer line. During a third time period, the method includes heating the second heating zone without heating the first heating zone to reinject the sample into a second transfer line.

In one aspect, a method for automated analysis of samples from a bioreactor is provided herein, the method including: drawing at least one sample from a bioreactor; pressurizing the drawn at least one sample into a sample flow; purifying at least one target protein in the sample flow using a first liquid chromatography apparatus to create a purified sample flow; splitting the purified sample flow into a purified sample fraction flow and an effluent flow; and, analyzing the at least one target protein in the purified sample fraction flow using a second liquid chromatography apparatus. Advantageously, the subject invention provides for an automated two-step liquid chromatography process utilizing first dimension liquid chromatography for purification and second dimension liquid chromatography for analysis.

An apparatus for separating a fluidic sample includes a fluid drive arrangement including fluid drive units for driving a mobile phase along a flow path to a sample separation unit, a sample accommodation volume for accommodating the fluidic sample and selectively fluidically coupleable with or decoupleable from the flow path, and a control unit. The control unit is configured to control pressure decoupling of at least part of at least one of the fluid drive units from the flow path, and enable the partially pressure-decoupled fluid drive unit(s) to pressurize the sample accommodation volume before fluidically coupling the sample accommodation volume with the flow path and/or to de-pressurize the sample accommodation volume after fluidically coupling the sample accommodation volume with the flow path for preparing a subsequent intake of fluidic sample in the sample accommodation volume.

Provided is a method for simultaneously detecting Vitamin K1 and Vitamin K2 in traces of blood. The method includes: constructing a two-dimensional liquid chromatography-tandem mass spectrometer, establishing an analytical method, and detecting at least three mixed standard solutions using the constructed two-dimensional liquid chromatography-tandem mass spectrometer to obtain a first detection result; fitting standard curve equations respectively corresponding to Vitamin K1 and Vitamin K2; and mixing and centrifuging a blood sample to which an extraction reagent and a certain amount of internal standard substance are added, collecting a supernatant, blowing the supernatant to dry with nitrogen, redissolving the residue, and detecting the dry supernatant using the constructed two-dimensional liquid chromatography-tandem mass spectrometer to obtain a second detection result. In this manner, concentrations of Vitamin K1 and Vitamin K2 in the blood sample are obtained.

The present disclosure provides methods for determining adsorption isotherms for complex mixtures. In at least one embodiment, a method for obtaining adsorption isotherms for liquid mixtures includes providing a column comprising an adsorbent. The method includes delivering a composition to the column, the composition comprising a multi-component feed and a solvent. The method includes collecting a sample from the column and introducing the sample to a two dimensional gas chromatograph to determine a time-series concentration of one or more components of the sample. The method includes integrating the time-series concentration of at least one of the one or more components to determine an isotherm of the at least one component. The method includes obtaining quantitative information of the at least one component, based on the isotherm of the at least one component.