Overcoming the Charged Ion Competition in Triple Quad Chemical Ionization Ion Source for Estimation of Celecoxib in Biological Matrix and its Application to Bioequivalence Study

AbstractThe purpose of the study was to develop and validate a sensitive, selective and reproducible method for the estimation of Celecoxib in human plasma. During the development, ion competition phenomenon observed in electrospray ionization ion source of liquid chromatography mass spectrometer system and in order to overcome it, different approaches applied. The Celecoxib and Celecoxib D7 in plasma were extracted by liquid-liquid extraction and separated in less than 4.0 min on a reverse phase C18 column, using isocratic elution with a binary mobile phase in the ratio of 70:30 v/v (Acetonitrile: 0.1% Ammonia Solution). Mass spectrometer was used as detector to quantitate the analytes in positive ion mode, using Atmospheric Pressure Chemical Ionization mode. Since the method was developed to perform the pharmacokinetic end point study for United States and Europe market, the method was fully validated, complying Food and Drug Administration, European Medicines Agency guideline and recommendations of American Association of Pharmaceutical Scientists white papers.

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Applications of Resonance Ionization Spectroscopy to Ultralow-Level Counting and Mass Spectroscopy

Radiocarbon ◽

10.1017/s0033822200009723 ◽

1980 ◽

Vol 22 (2) ◽

pp. 428-434 ◽

Cited By ~ 15

Author(s):

S D Kramer ◽

G S Hurst ◽

J P Young ◽

M G Payne ◽

M K Kopp ◽

...

Keyword(s):

Mass Spectrometer ◽

Mass Spectroscopy ◽

Ion Source ◽

Resonance Ionization ◽

Parent Species ◽

Resonance Ionization Spectroscopy ◽

Mass Spectrometer System ◽

Spectrometer System ◽

Delayed Time ◽

Time Coincidence

In this paper it is shown that the ability to directly detect a daughter atom, using resonance ionization spectroscopy, in delayed time coincidence with the decay of a parent species promises to drastically reduce the background in low-level counting experiments. In addition, resonance ionization can also be used as an ion source for a mass spectrometer system that is capable of discriminating between isobars.

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Development and application of a C− ion source and extraction system to a high resolution mass spectrometer system

10.1063/1.44760 ◽

1992 ◽

Cited By ~ 1

Author(s):

A. T. Young ◽

C. Y. Li ◽

C. F. Chan ◽

K. N. Leung

Keyword(s):

High Resolution ◽

Mass Spectrometer ◽

Ion Source ◽

Extraction System ◽

High Resolution Mass ◽

Mass Spectrometer System ◽

Spectrometer System ◽

High Resolution Mass Spectrometer ◽

Resolution Mass

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Online 13C and 14C Gas Measurements by EA-IRMS–AMS at ETH Zürich

Radiocarbon ◽

10.1017/rdc.2016.68 ◽

2016 ◽

Vol 59 (3) ◽

pp. 893-903 ◽

Cited By ~ 23

Author(s):

Cameron P McIntyre ◽

Lukas Wacker ◽

Negar Haghipour ◽

Thomas M Blattmann ◽

Simon Fahrni ◽

...

Keyword(s):

Mass Spectrometer ◽

Global Carbon Cycle ◽

Ion Source ◽

Data Sets ◽

Accelerator Mass Spectrometer ◽

Mass Spectrometer System ◽

Gas Measurements ◽

Rich Data ◽

Spectrometer System ◽

Global Carbon

AbstractStudies using carbon isotopes to understand the global carbon cycle are critical to identify and quantify sources, sinks, and processes and how humans may impact them. 13C and 14C are routinely measured individually; however, there is a need to develop instrumentation that can perform concurrent online analyses that can generate rich data sets conveniently and efficiently. To satisfy these requirements, we coupled an elemental analyzer to a stable isotope mass spectrometer and an accelerator mass spectrometer system fitted with a gas ion source. We first tested the system with standard materials and then reanalyzed a sediment core from the Bay of Bengal that had been analyzed for 14C by conventional methods. The system was able to produce %C, 13C, and 14C data that were accurate and precise, and suitable for the purposes of our biogeochemistry group. The system was compact and convenient and is appropriate for use in a range of fields of research.

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The Influence of Doping on the Etching of Si(111)

MRS Proceedings ◽

10.1557/proc-75-443 ◽

1986 ◽

Vol 75 ◽

Author(s):

Harold F. Winters ◽

D. Haarer

Keyword(s):

Mass Spectrometer ◽

Doping Level ◽

Etch Rate ◽

Plasma Reactors ◽

Doping Effects ◽

Mass Spectrometer System ◽

Spectrometer System

AbstractIt has been recognized for some time that the doping level in silicon influences etch rate in plasma environments[1–8]. We have now been able to reproduce and investigate these doping effects in a modulated-beam, mass spectrometer system described previously [9] using XeF2 as the etchant gas. The phenomena which have been observed in plasma reactors containing fluorine atoms are also observed in our experiments. The data has led to a model which explains the major trends.

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