Thermo Finnigan LLC

Thermo Fisher Scientific (Bremen) Gmbh

Eloy R Wouters

Joshua A Silveira

Maurizio Splendore

Alexander Alekseevich Makarov

R Paul Atherton

Jean Jacques Dunyach

Viatcheslav V Kovtoun

Jean-Jacques Dunyach

Michael L Poltash

Viacheslav I Kozlovskiy

Paul R Atherton

Mikhail G Skoblin

Michael W Senko

Gary A Schultz

Christopher Mullen

Satendra Prasad

Wei Wei

Rohan A Thakur

Jae C Schwartz

Bennett S Kalafut

Brandon Howard Robson

David E Minkler

William Siebert

Brian D Adamson

Abhishek Joshi

Dale Lindseth

Maurizio Spendore

A mass spectrometry method comprises: (a) introducing ions and gas into a first electrode section of an ion transport apparatus along an axis, the ion transport apparatus further comprising a second electrode section including: a plurality of stacked, mutually parallel ring or plate electrodes; and an ion outlet aperture configured to receive the ions from the second electrode section and to transfer the ions to the vacuum chamber; (b) providing only non-oscillatory voltages to electrodes of the first electrode section of the ion transport apparatus that divert motion of the ions away from that axis and towards an entrance aperture of the second electrode section; (c) transporting the ions through the second electrode section to and through the ion outlet aperture to the vacuum chamber; and (d) removing a major portion of the gas through an exhaust port that is offset from the ion outlet aperture.

Complemented ion funnel for mass spectrometer

A mass spectrometry method comprises: (1) introducing ions and gas into an first electrode section of an ion transport apparatus through a slot of an ion transfer tube, the ion tunnel section comprising a first longitudinal axis that is contained within a slot plane of the ion transfer tube, the first longitudinal axis not intersecting an outlet of the ion transfer tube, wherein the apparatus further comprises: (a) a second electrode section configured to receive the ions from the first electrode section and comprising a second longitudinal axis that is not coincident with the first longitudinal axis; and (b) an ion outlet aperture; (2) providing voltages to electrodes of the ion transport apparatus that urge the ions to migrate towards the first longitudinal axis within the first electrode section; and (3) exhausting gas through a port that is offset from the ion outlet aperture.

Packed-tip electrospray ionization (ESI) emitters for mass spectrometry are described. In one aspect an ESI emitter stores a first type of particle. A liquid chromatography (LC) column is coupled with the emitter via a junction. The LC column stores a different type of particle than the ESI emitter to facilitate better chromatographic and ESI performance.

Packed tip electrospray emitter

An electrospray ionization system used in mass spectrometry provides for improved current measurement. The system includes a fluid union, a fluid column coupled with a first port of the fluid union, a power source coupled with the fluid union and configured to apply a voltage potential to the fluid union, and an electrospray emitter coupled with a second port of the fluid union. The power source is coupled with the first port and configured to apply the voltage potential to the first port to restrict current leakage from the fluid union. The current sensing circuit is configured to determine an electrical current flow between the power source and the at least one of the fluid union and the first port.

Electrospray current measurement in the nanospray and microspray regime

A method for cleaning an electrospray emitter of a mass spectrometer comprises the steps of: (a) changing a mode of operation of the electrospray emitter from a stable jet mode of operation to a dripping mode or a pulsating mode of operation by lowering a magnitude, |V|, of a voltage applied between a counter electrode and the electrospray emitter; and (b) changing the mode of operation of the electrospray emitter from the dripping mode or the pulsating mode of operation to the stable jet mode of operation by increasing the magnitude, |V|, of the applied voltage; wherein the repetitions are performed at a predetermined frequency that depends on one or more of liquid flow rate, an emitter internal diameter, and liquid properties.

Method and apparatus for improved electrospray emitter lifetime

An optimization control system may receive mass spectra of ions emitted from an ionization emitter toward an inlet of a mass spectrometer and control, based on the mass spectra, an automated motion system to adjust a position of the emitter relative to the inlet.

Optimizing mass spectra signal quality

A method of reducing fragmentation of ions generated from a sample during transport of the ions through an ion transport apparatus that comprises an ion funnel portion, comprises: applying a selected DC potential difference between an outlet end of the ion transport apparatus and an exit ion lens that is disposed adjacent to the outlet end, wherein a sign of the selected DC potential difference is chosen so as to accelerate the ions from the outlet end of the ion transport apparatus towards and through the exit ion lens.

Ion funnels and systems incorporating ion funnels

A method for cleaning a first electrospray emitter of a mass spectrometer comprises: changing an operating mode of the first electrospray emitter from a stable jet mode of operation to a dripping or pulsating mode of operation by lowering a magnitude of a voltage applied between a counter electrode and the first electrospray emitter, |V|; moving the first electrospray emitter from a first emitter position from which electrospray ions are delivered to a mass spectrometer inlet to a second emitter position and, simultaneously, moving a second electrospray emitter from a third emitter position to a fourth emitter position; causing a cleaning solvent to flow through the first electrospray emitter at least until a droplet of the cleaning solvent forms on an exterior surface of the first electrospray emitter while operating the electrospray emitter in the dripping mode of operation; and causing the droplet to dislodge from the emitter exterior.

Using ion mobility separation to improve a duty cycle of a mass spectrometer is described. In one aspect, a mass spectrometer can use an ion-mobility spectrometer to allow for more multiply-charged ions to transmit through than singly-charged ions. This results in a mass analyzer to perform a mass analysis with more multiply-charged ions.

Duty cycle improvement for a mass spectrometer using ion mobility separation

An electrospray ion source for a mass spectrometer comprises: (i) a plurality of N electrospray emitters within an ionization compartment, wherein N&#x2265;2; (ii) a mixing chamber; (iii) a plurality of N inlets, each inlet comprising a conduit configured to receive charged particles from a respective one of the electrospray emitters and to emit the charged particles into the mixing chamber; (iv) an outlet port either facing or within an intermediate-vacuum compartment; and (v) a heater in thermal contact with at least a portion of the mixing chamber.

Multi-electrospray ion source for a mass spectrometer

An ion transport system comprises: (I) an ion transfer tube extending between an atmospheric-pressure ionization chamber and a partially evacuated chamber; and (II) an ion funnel within the chamber comprising: (1) an exit electrode that has an exit aperture configured to deliver the gas and charged particles to a high-vacuum chamber; and (2) a funnel portion comprising a plurality of plate electrodes configured as a stack, each electrode comprising a respective aperture, wherein an aperture diameter of each of the plurality of electrodes is greater than or equal to three times an inter-electrode pitch and wherein no DC electrical potential gradient is applied between the exit electrode and an adjacent one of the plurality of plate electrodes.

A method for cleaning an electrospray emitter of a mass spectrometer, comprises: (a) changing a mode of operation of the electrospray emitter from a stable jet mode of operation to a dripping mode or a pulsating mode of operation by lowering a magnitude of a voltage applied between an counter electrode and the electrospray emitter; (b) causing a cleaning solvent to flow through the electrospray emitter at least until a droplet of the cleaning solvent forms on an exterior surface of the electrospray emitter while operating the electrospray emitter in the dripping mode of operation; and (c) causing the droplet to dislodge from the electrospray emitter exterior.

A system for analyzing a sample includes a chromatographic device, an electrospray source, and a mass resolving device. The chromatographic device is configured to separate components of the sample as a function of retention time within a chromatographic column. The electrospray source is configured to direct a first portion of a flow from the chromatographic device via a waste outlet to a pressurized waste reservoir, direct a second portion of the flow to an electrospray ionization outlet to form a spray, and charge and desolvate the spray to form ions of the components of the sample. A flow rate of the second portion of the liquid flow is substantially determined by a pressure of the pressurized waste reservoir. The mass resolving device configured to receive the ions and characterize the mass-to-charge ratio of the ions.

Systems and methods for ionization

An ion separation device comprising a plurality of electrodes arranged in a two-dimensional grid, a gas supply configured to provide a gas flow along the first direction, and an ion inlet arranged to receive ions. The plurality of electrodes is configured to create one or more pseudopotential barriers of increasing magnitude along a first direction. A drag force is applied to the ions by the gas flow is opposed by a pseudopotential gradient of the plurality of electrodes.

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San Jose, CA, United States of America

Eloy R Wouters