A sample separation apparatus includes a first-dimension separation unit for separating the fluidic sample, having a first-dimension outlet for outputting the fluidic sample or fractions thereof, and a second-dimension separation unit for further separating the fluidic sample or fractions thereof. The second-dimension separation unit has a second-dimension inlet fluidically coupled to the first-dimension outlet. A modulation unit, coupled between the first-dimension outlet and the second-dimension inlet at a first coupling point, is configured for withdrawing fluid from the first coupling point and for ejecting fluid into the first coupling point. A second-dimension fluid drive is coupled to a second coupling point located between the first-dimension outlet and the second-dimension inlet and downstream from the first coupling point. The second-dimension fluid drive is configured for generating a fluid flow for driving at least part of the fluidic sample after treatment by the first-dimension separation unit through the second-dimension separation unit.

Provided are methods for determining the apolipoprotein E (ApoE) phenotype in a sample by mass spectrometry; wherein the ApoE allele(s) present in the sample is determined from the identity of the ions detected by mass spectrometry. In another aspect, provided herein are methods for diagnosis or prognosis of Alzheimer's disease or dementia.

A method of manufacturing oxytocin or oxytocin receptor agonist comprising a step of combining an antisolvent with a solution comprising oxytocin or oxytocin receptor agonist so as to precipitate a product oxytocin or a product oxytocin receptor agonist from the solution.

The present disclosure relates to methodologies, systems, apparatus, kits, and microfluidic separation devices based on separation columns and restrictors that are matched and bundled together for distribution as a unit, where the mobile phase flow rate and post-column pressure are specified based on this combination of matched separation column and restrictor.

The present disclosure relates to methodologies, systems, apparatus, and kits for diagnosing the condition of a restrictor element in a chromatography system based on flow rate measurements, or pressure measurements, or both.

Disclosed herein are methods of determining load volumes for capture chromatography in system and methods for continuous manufacture of a biological product.

Disclosed is a gradient proportioning valve for liquid chromatography that includes a plurality of inlet ports configured to receive a plurality of fluids, a manifold connected to each of the plurality of inlet ports configured to mix the plurality of fluids in a controlled manner to provide a fluid composition, the manifold including a plurality of conduits internal to the manifold, each of the plurality of conduits receiving fluid through a respective one of the plurality of inlet ports, an actuation mechanism having a piston located within a bored structure surrounding the piston, the actuation mechanism configured to open and close at least one of the plurality of conduits in a controlled manner where the piston and the bored structure have a tight tolerance configured to create a fluid tight seal, and a common outlet port configured to receive the fluid composition.

A method for controlling the flow of liquid in a high performance liquid chromatography apparatus. The method includes operating a pump, measuring the liquid pressure downstream of the pump, measuring the liquid flow rate downstream of the pump, and controlling the operation of the pump. In the method, it is automatically determined whether the pump is controlled to achieve a desired pressure or controlled to achieve a desired flow rate. Fuzzy logic can be applied in the method to determine the switch between the control modes.

A reconfigurable capillary liquid chromatography system includes a solvent delivery manager including a first solvent pump assembly including a first pump housing or mount. A base module is further provided including a base module housing which is user accessible, or a base module bracket, and an injection valve for sample injection to a liquid chromatography column. The injection valve has an inlet port for receiving a sample and the injection valve is mounted in or on the base module housing or the base module bracket. The solvent delivery manager is configured to deliver solvent to the injection valve. A reconfigurable control system is also provided for controlling the reconfigurable capillary liquid chromatography system.

A liquid chromatography system and method utilizes a mobile phase comprising liquified compressible gas and miscible organic solvents. The compressible fluid may be carbon dioxide (CO2). Liquid CO2 tapped from an existing source is depressurized through a flow control metering station before adding solvent. The mobile phase flows through a sample vessel containing analytes and chromatography column for sample separation. A back pressure regulator maintains a set elution pressure in the chromatography column. CO2 advantageously remains in liquid phase for elution in the column, thereby avoiding two-phase conditions adversely affecting analyte resolution. An equilibration bypass flow loop may be provided to separate normal sample elution from initial CO2 flow equilibration, thereby allowing rapid exchange of samples with minimal downtime. System CO2 pressures less than 100 bar and room temperature may be used during the process, thereby obviating the need for high pressure pumps and chillers of supercritical fluid chromatography.