Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
Systems and methods are disclosed for timed introduction of samples into a mass spectrometer may include receiving a plurality of sample ion pulses in a mass spectrometer from a sampling interface, where the sample ion pulses are received at a pre-determined time pattern; detecting the received sample ion pulses to generate a signal; isolating an analyte signal by signal conditioning the generated signal based on the pre-determined time pattern; and identifying a presence of an analyte based on the isolated analyte signal. The signal conditioning may include pulse-based averaging based on the pre-determined time pattern or may include converting the generated signal to a frequency-domain signal and calculating a modulus to isolate the analyte signal. The pre-determined time pattern may be periodic where the signal conditioning comprises performing a Fourier Transform on the signal to convert it to a frequency-domain signal.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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 μA, for example, without the electric potential between the electrospray electrode and the counter electrode initiating the electrical discharge avalanche that results from the dielectric break-down of the air gap therebetween, which can cause sputtering and effect the long-term operation of the ESI source.