Abstract: A fluid processing system that can include a sample container having a sample chamber for containing a fluid and a plurality of magnetic particles and at least one movable magnetic assembly configured to be movably inserted into or out of the sample chamber. The movable magnetic assembly can include a plurality of electromagnets that generate a magnetic field within at least a portion of the sample chamber when the assembly is inserted at least partially into the sample chamber. The fluid processing system can also include a signal generator that applies electrical signals, e.g., AC electrical signals, to the electromagnets of the magnetic assembly and a controller coupled to the signal generator that is configured to control phases of the electrical signals applied to the electromagnets to generate magnetic field gradients within the portion of the sample chamber effective to magnetically influence the plurality of the magnetic particles.

Abstract: An ultrasonic transmitter (95) and detector (e.g., integrated as an ultrasound transducer) utilized in a feedback control system automatically monitors and/or detects surface profile (e.g., shape) of the liquid-air interface and adjusts the flow rate of sampling liquid to ensure that experimental conditions remain consistent at the time of sample introduction during serial samplings. The feedback control can provide for automated adjustment of the surface profile of the liquid-air interface in accordance with changes in desired set point according to an experimental workflow (e.g., automated adjustment between an interface corresponding to a vortex sampling set point and an overflow cleaning set point).

Abstract: Mass spectrometer based analytical systems and methods in which a feedback control system can be utilized to control the flow of liquid within a sampling probe to adjust and/or maintain the surface profile (e.g., shape) of the liquid-air interface within an open sampling port of the sampling probe. The feedback control systems can automatically monitor and/or detect the surface profile of the liquid-air interface and adjust the flow rate of the sampling liquid to ensure that experimental conditions remain consistent at the time of sample introduction during serial samplings. These can provide stable and reproducible analyte flows of consistent dilution to the ion source, increasing reproducibility and/or accuracy of data generated by MS analysis. Can be used with a change in the desired set point according to the particular experimental workflow (e.g., automated adjustment between an interface corresponding to a sampling set point and a cleaning set point).

Abstract: A system and method are provided for loading a sample into an analytical instrument using acoustic droplet ejection (“ADE”) in combination with a continuous flow sampling probe. An acoustic droplet ejector is used to eject small droplets of a fluid sample containing an analyte into the sampling tip of a continuous flow sampling probe, where the acoustically ejected droplet combines with a continuous, circulating flow stream of solvent within the flow probe. Fluid circulation within the probe transports the sample through a sample transport capillary to an outlet that directs the analyte away from the probe to an analytical instrument, e.g., a device that detects the presence, concentration quantity, and/or identity of the analyte. When the analytical instrument is a mass spectrometer or other type of device requiring the analyte to be in ionized form, the exiting droplets pass through an ionization region, e.g.

Abstract: Apparatus, systems, and methods in accordance with various aspects of the applicant's teachings provide for improved interfaces for providing a sample flow from a sample conduit (e.g., an analytical conduit or capillary), including those used in sample separation techniques such as CE and HPLC, to an ESI source for ionization thereby.

Abstract: Methods and systems for delivering a liquid sample to an ion source for the generation of ions and subsequent analysis by mass spectrometry are provided herein. In accordance with various aspects of the present teachings, MS-based systems and methods are provided in which the flow of desorption solvent within a sampling probe fluidly coupled to an ion source can be selectively controlled such that one or more analyte species can be desorbed from a sample substrate inserted within the sampling probe within a decreased volume of desorption solvent for subsequently delivery to the ion source. In various aspects, sensitivity can be increased due to higher desorption efficiency (e.g., due to increased desorption time) and/or decreased dilution of the desorbed analytes.

Abstract: Methods and apparatus for processing fluids are described. In various aspects, a fluid processing system may include a magnetic assembly that includes a plurality of magnetic structures configured to generate a magnetic field gradient within a fluid container. The magnetic structures may be formed as a plurality of electromagnets configured to be individually actuated by a controller. Each of the electromagnets may generate a magnetic field within the fluid container. The electromagnets may be differentially actuated to create a magnetic field gradient within the fluid container to agitate, mix, or otherwise influence magnetic particles disposed within the fluid container. Activation of the electromagnets of an electromagnetic structure may generate a magnetic field gradient that influences magnetic particles in an x-y direction.

Abstract: Methods and apparatus for processing fluids are described. In various aspects, a fluid processing system may include a magnetic assembly that includes a plurality of magnetic structures configured to generate a magnetic field gradient within a fluid container. The magnetic structures may be formed as a plurality of electromagnets configured to be individually actuated by a controller. Each of the electromagnets may generate a magnetic field within the fluid container. The electromagnets may be differentially actuated to create a magnetic field gradient within the fluid container to agitate, mix, or otherwise influence magnetic particles disposed within the fluid container. Activation of the electromagnets of an electromagnetic structure may generate a magnetic field gradient that influences magnetic particles in an x-y direction.

Abstract: Methods and systems for delivering a liquid sample to an ion source for the generation of ions and subsequent analysis by mass spectrometry are provided herein. In accordance with various aspects of the present teachings, MS-based systems and methods are provided in which a desorption solvent utilized in a sampling interface to desorb one or more analyte species from an SPME device is fluidly coupled to an ion source for ionizing the one or more analyte species desorbed into the desorption solvent for subsequent mass spectrometric analysis (e.g., without a liquid chromatography (LC) column between the sampling interface and the ion source).

Abstract: Methods and systems for delivering a liquid sample to an ion source for the generation of ions and subsequent analysis by mass spectrometry are provided herein. In accordance with various aspects of the present teachings, MS-based systems and methods are provided in which a desorption solvent utilized in a sampling interface to desorb one or more analyte species from an SPME device is fluidly coupled to an ion source for ionizing the one or more analyte species desorbed into the desorption solvent for subsequent mass spectrometric analysis (e.g., without a liquid chromatography (LC) column between the sampling interface and the ion source).

Abstract: A precision flow controller is capable of providing a flow rate less than 100 microliters/minute and varying the flow rate in a prescribed manner that is both predictable and reproducible where the accuracy and precision of the flowrate is less than 5% of the flow rate. A plurality of variable pressure fluid supplies pump fluid through a single outlet. Flowmeters measure the flow rates and a controller compares the flow rates to desired flowrates and, if necessary, adjusts the plurality of variable pressure fluid supplies so that the variable pressure fluid supplies pump fluid at the desired flow rate. The variable pressure fluid supplies can be pneumatically driven.

Abstract: A junction is made between a first microfluidic substrate (12) having an elongate component (303) protruding from it and a second microfluidic substrate (22) having a corresponding conduit (261). Each of the substrates has a pair of alignment features, for example planar orthogonal surfaces (13, 15; 23, 25) or grooves (141, 151; 241, 251) in opposite sides of the substrate. The substrates are placed on an alignment jig 6 having location features (63, 65) corresponding to the alignment features. The elongate component can be surrounded by a compressible gasket 40). The substrates are pushed towards each other so that the elongate component enters the conduit and the gasket, if any, is compressed. A fluid-tight junction results so long as the substrates are maintained in the necessary position, either by permanent means, or, if a junction which can be disassembled is needed, by maintaining pressure between the substrates.

Abstract: A precision flow controller is capable of providing a flow rate less than 100 microliters/minute and varying the flow rate in a prescribed manner that is both predictable and reproducible where the accuracy and precision of the flowrate is less than 5% of the flow rate. A plurality of variable pressure fluid supplies pump fluid through a single outlet. Flowmeters measure the flow rates and a controller compares the flow rates to desired flowrates and, if necessary, adjusts the plurality of variable pressure fluid supplies so that the variable pressure fluid supplies pump fluid at the desired flow rate. The variable pressure fluid supplies can be pneumatically driven.

Abstract: A precision flow controller is capable of providing a flow rate less than 100 microliters/minute and varying the flow rate in a prescribed manner that is both predictable and reproducible where the accuracy and precision of the flowrate is less than 5% of the flow rate. A plurality of variable pressure fluid supplies pump fluid through a single outlet. Flowmeters measure the flow rates and a controller compares the flow rates to desired flowrates and, if necessary, adjusts the plurality of variable pressure fluid supplies so that the variable pressure fluid supplies pump fluid at the desired flow rate. The variable pressure fluid supplies can be pneumatically driven.

Abstract: A microfluidic detection device provides reduced dispersion of axial concentration gradients in a flowing sample. The microfluidic detection device includes a cell body and a flow path through the cell body. The flow path has an inlet segment, an outlet segment, and a central segment, which forms a detection cell. The central segment is located between and at an angle with both the inlet segment and the outlet segment. The central segment has a first junction with the inlet segment and a second junction with the outlet segment. The cell body contains two arms that can transmit light to and from the detection cell. At least a portion of a first arm is located in the first junction and at least a portion of a second arm is located in the second junction. The portions of the arms located in the junctions are situated so that fluid entering or exiting the central segment of the flow path flows around the outer surface of one of the portions.

Abstract: A junction is made between a first microfluidic substrate (12) having an elongate component (303) protruding from it and a second microfluidic substrate (22) having a corresponding conduit (261). Each of the substrates has a pair of alignment features, for example planar orthogonal surfaces (13, 15; 23, 25) or grooves (141, 151; 241, 251) in opposite sides of the substrate. The substrates are placed on an alignment jig 6 having location features (63, 65) corresponding to the alignment features. The elongate component can be surrounded by a compressible gasket 40). The substrates are pushed towards each other so that the elongate component enters the conduit and the gasket, if any, is compressed. A fluid-tight junction results so long as the substrates are maintained in the necessary position, either by permanent means, or, if a junction which can be disassembled is needed, by maintaining pressure between the substrates.

Abstract: A junction is made between a first microfluidic substrate (12) having an elongate component (303) protruding from it and a second microfluidic substrate (22) having a corresponding conduit (261). Each of the substrates has a pair of alignment features, for example planar orthogonal surfaces (13,15; 23,25) or grooves (141,151; 241, 251) in opposite sides of the substrate. The substrates are placed on an alignment jig 6 having location features (63, 65) corresponding to the alignment features. The elongate component can be surrounded by a compressible gasket 40). The substrates are pushed towards each other so that the elongate component enters the conduit and the gasket, if any, is compressed. A fluid-tight junction results so long as the substrates are maintained in the necessary position, either by permanent means, or, if a junction which can be disassembled is needed, by maintaining pressure between the substrates.

Abstract: A microfluidic processing system having a manifold with at least one inlet; at least one outlet; and a plurality of microfluidic chip holders. A fluidic jumper is coupled to one of the chip holders and at least two fluidic elements are coupled to at least one of the chip holders. The fluidic jumper controls the fluidic path through the system.

Abstract: Microfluidic systems including a principal microfluidic conduit (24), an adjacent dead volume (1) and a drain conduit (70) which mitigates the adverse effects of the dead volume on the operation of the system.

Abstract: A heat transfer system comprising a primary heat exchanger for receiving heat from a heat source; a secondary heat exchanger for exhausting heat to a heat sink; a conduit connecting the primary heat exchanger and the secondary heat exchanger; and an electrokinetic pump for pumping a heat exchange fluid between the primary heat exchanger and the secondary heat exchanger through the conduit.