Dh Technologies Development Pte. Ltd.

Peter Kovarik

Thomas R Covey

John J Corr

Bradley B Schneider

Chang Liu

Gordana Ivosev

Brett Barnett

Michael Bailey

A trace of intensity versus time values is received for a series of samples produced by a mass spectrometer. Also, a series of ejections times corresponding to the series of samples produced by a sample introduction system is received. A series of expected peak times corresponding to the series of ejection times are calculated using a known delay time from ejection to mass analysis. At least one isolated peak of the trace is identified using the series of expected peak times. A peak profile is calculated by fitting a mixture of at least two different distribution functions to the at least one isolated peak. For at least one time of the series of expected peak times, an area of a peak at the one time is calculated by fitting the peak profile to the trace at the one time and calculating an area of the fitted peak profile.

Method for increased throughput

An ion source assembly for use in a mass spectrometry system comprises a housing defining an ionization chamber disposed in fluid communication with a sampling orifice of a mass spectrometer system. The housing defines a first opening for coupling to a first electrospray probe to discharge a liquid sample at flow rates greater than a nanoflow range along a longitudinal axis that is substantially orthogonal to a central axis of the sampling orifice. An elongate auxiliary electrode assembly extends from the housing to an electrically conductive distal end disposed in the ionization chamber such that the electrically conductive distal end is disposed substantially on the central axis of the sampling orifice. The electrically conductive distal end may be coupled to a power supply to generate an electric field to improve the desolvation of the sample plume and the transport of ions ejected from the sample plume into the sampling orifice.

Electrospray ion source assembly

An electrospray ionization emitter according to various aspects described herein can include an emitter body formed using fused silica. The emitter body can comprise a fluid conduit segment that includes a liquid connection end that has been coated with polyetheretherketone (PEEK) on at least one portion thereof. The liquid connection end can have a first outer diameter that is configured to be connected to a sample source to receive a sample liquid for ionization therefrom. The emitter body can further comprise an ionization discharge segment that is fluidly connected to the fluid conduit segment. The ionization discharge segment can have an ionization discharge end that is coated with a conductive material on at least one portion thereof and configured to have a second outer diameter that allows ionization of the liquid sample.

Integrated electrospray emitter and methods for making same

In one aspect, an ion source for use in a mass spectrometry system is disclosed, which comprises a housing, a first and a second ion probe coupled to said housing, and a first and a second emitter configured for coupling, respectively, to said first and second ion probes. The first ion probe is configured for receiving a sample at a flow rate in nanoflow regime and the second ion probe is configured for receiving a sample at a flow rate above the nanoflow regime. Each of the ion probes includes a discharge end (herein also referred to as the discharge tip) for ionizing at least one constituent of the received sample. In some embodiment, each ion probe receives the sample from a liquid chromatography (LC) column. Further, the ion probes can be interchangeably disposed within the housing.

Integrated electrospray ion source

Systems and methods for atmospheric pressure chemical ionization are provided herein. In various aspects, the APCI apparatus, systems, and methods can provide an asymmetric sample spray into a vaporization chamber asymmetrically (e.g., off axis from the longitudinal axis of the vaporization chamber) so as to increase the interaction of the molecules in the sample spray with the vaporization chamber's sidewalls (and expose more of the molecules to the heat generated thereby), which can thereby result in improved consistency and/or efficiency of ion formation, and/or increased sensitivity relative to conventional APCI techniques.

APCI ion source with asymmetrical spray

Methods and systems are provided for reducing the occurrence of unwanted electrical discharge when operating an electrospray ion source to generate ions for mass spectrometric analysis. In accordance with various aspects of the applicant's teachings, the methods and systems described herein can provide for controlling the ion emission current so as to limit the onset of avalanche of electrical discharge between the electrospray electrode and the counter electrode under ionization conditions that typically tend to increase the likelihood of such discharge (arcing), while nonetheless providing for maximal ionization efficiency. In various aspects, emission currents between the electrospray electrode and the counter electrode through which the ions are transmitted to a downstream mass analyzer can be maintained at elevated levels, below 10 &#x3bc;A, for example, without the electric potential between the electrospray electrode and the counter electrode initiating the electrical discharge avalanche that results from the dielectric breakdown of the air gap therebetween, which can cause sputtering and effect the long-term operation of the ESI source.

System for minimizing electrical discharge during ESI operation

Methods and systems for delivering a liquid sample to an ion source are provided herein: In various aspects, the methods and systems described herein can utilize the flow provided by an LC pump(s) to drive a calibration fluid to an ion source of a mass spectrometer system. In various aspects, methods and systems described herein can additionally or alternatively be placed upstream of an LC column for providing an elution gradient of a plurality of solvents, without requiring a plurality of pumps and/or separate mixing elements.

Systems and methods for delivering liquid to an ion source

Systems and methods for delivering a sample to a mass spectrometer are provided. In one aspect, the systems and methods can provide efficient cooling of an ion source probe to prevent overheating and the resulting degradation in ion sampling. In some aspects, such cooling can result in improved consistency and/or efficiency of ion formation. Moreover, ion source cooling in accordance with various aspects of the present teachings can allow for the use of higher temperatures in the ionization chamber (thereby improving desolvation) and/or can enable the use of lower flow rate sample sources than with conventional techniques.

Ion source for mass spectrometry

Systems and methods for delivering a sample to a mass spectrometer are provided. In one aspect, the system can include a sample source for generating a sample plume entrained in a primary gas stream in a first flow direction at a first flow rate, and a gas source for generating a secondary gas stream along a second flow direction different from the first flow direction and at a second flow rate greater than the first flow rate. The sample source and the gas source can be positioned relative to one another such that the primary gas stream intersects the secondary gas stream so as to generate a resultant gas stream propagating along a trajectory different from said first and second direction to bring the sample to proximity of a sampling orifice of the mass spectrometer.

Methods and systems for generating ions from a liquid sample for mass spectrometry are provided herein. In various aspects, the methods and systems can enhance the break-up of a jet of the liquid sample upon injection into an ionization chamber. In some aspects, methods and systems perturb the liquid sample prior to discharge to increase the internal energy of the sample so as to enhance the formation of liquid droplets when the liquid sample is injected into the ionization chamber.

Enhanced spray formation for liquid samples

Methods and systems for delivering a liquid sample to an ion source are provided herein. In various aspects, the methods and systems can improve the stability of a flow of liquid sample delivered to an ion source. In accordance with various aspects, the methods and systems can remove bubbles (e.g., cavitation bubbles or otherwise) present in the liquid sample prior to its injection into an ionization chamber.

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Markham, Canada

Peter Kovarik