Optimization of parameters affecting signal intensity in an LTQ-orbitrap in negative ion mode: A design of experiments approach

Reactions carried out in the presence of rubber septa run the risk of additives being leached out by the solvent. Normally, such species are present at low enough levels that they do not interfere with the reaction significantly. However, when studying reactions using sensitive methods such as mass spectrometry, the appearance of even trace amounts of material can confuse dynamic analyses of reactions. A wide variety of additives are present in rubber along with the polymer: antioxidants, dyes, detergent, and vulcanization agents, and these are all especially problematic in negative ion mode. A redesigned Schlenk flask for pressurized sample infusion (PSI) is presented as a means of practically eliminating the presence of contaminants during reaction analyses.

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Confounding contaminants in mass spectrometric reaction monitoring

10.26434/chemrxiv.7488737.v2 ◽

2019 ◽

Author(s):

Gilian T. Thomas ◽

Landon MacGillivray ◽

Natalie L. Dean ◽

Rhonda L. Stoddard ◽

Lars Yunker ◽

...

Keyword(s):

Mass Spectrometry ◽

Mass Spectrometric ◽

Negative Ion ◽

Reaction Monitoring ◽

Schlenk Flask ◽

Dynamic Analyses ◽

Rubber Septa ◽

Negative Ion Mode ◽

Mode A

Reactions carried out in the presence of rubber septa run the risk of additives being leached out by the solvent. Normally, such species are present at low enough levels that they do not interfere with the reaction significantly. However, when studying reactions using sensitive methods such as mass spectrometry, the appearance of even trace amounts of material can confuse dynamic analyses of reactions. A wide variety of additives are present in rubber along with the polymer: antioxidants, dyes, detergent, and vulcanization agents, and these are all especially problematic in negative ion mode. A redesigned Schlenk flask for pressurized sample infusion (PSI) is presented as a means of practically eliminating the presence of contaminants during reaction analyses.

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Confounding contaminants in mass spectrometric reaction monitoring

10.26434/chemrxiv.7488737 ◽

2019 ◽

Author(s):

Gilian T. Thomas ◽

Landon MacGillivray ◽

Natalie L. Dean ◽

Rhonda L. Stoddard ◽

Lars Yunker ◽

...

Keyword(s):

Mass Spectrometry ◽

Mass Spectrometric ◽

Negative Ion ◽

Reaction Monitoring ◽

Schlenk Flask ◽

Dynamic Analyses ◽

Rubber Septa ◽

Negative Ion Mode ◽

Mode A

Reactions carried out in the presence of rubber septa run the risk of additives being leached out by the solvent. Normally, such species are present at low enough levels that they do not interfere with the reaction significantly. However, when studying reactions using sensitive methods such as mass spectrometry, the appearance of even trace amounts of material can confuse dynamic analyses of reactions. A wide variety of additives are present in rubber along with the polymer: antioxidants, dyes, detergent, and vulcanization agents, and these are all especially problematic in negative ion mode. A redesigned Schlenk flask for pressurized sample infusion (PSI) is presented as a means of practically eliminating the presence of contaminants during reaction analyses.

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Dopant-Enriched Nitrogen Gas for Enhanced Electrospray Ionization of Released Glycans in Negative Ion Mode

Analytical Chemistry ◽

10.1021/acs.analchem.1c00023 ◽

2021 ◽

Author(s):

Katarina Madunić ◽

Sander Wagt ◽

Tao Zhang ◽

Manfred Wuhrer ◽

Guinevere S.M. Lageveen-Kammeijer

Keyword(s):

Electrospray Ionization ◽

Negative Ion ◽

Nitrogen Gas ◽

Negative Ion Mode

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A comparative study of the fragmentation of neutral lactooligosaccharides in negative-ion mode by UV-MALDI-TOF and UV-MALDI ion-trap/TOF mass spectrometry

Journal of the American Society for Mass Spectrometry ◽

10.1016/j.jasms.2005.09.004 ◽

2006 ◽

Vol 17 (1) ◽

pp. 67-74 ◽

Cited By ~ 33

Author(s):

Tohru Yamagaki ◽

Hiroaki Suzuki ◽

Kazuo Tachibana

Keyword(s):

Mass Spectrometry ◽

Comparative Study ◽

Ion Trap ◽

Negative Ion ◽

Maldi Tof ◽

Negative Ion Mode

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Fast Sensing of Hydrogen Cyanide (HCN) Vapors Using a Hand-Held Ion Mobility Spectrometer with Nonradioactive Ionization Source

Sensors ◽

10.3390/s21155045 ◽

2021 ◽

Vol 21 (15) ◽

pp. 5045

Author(s):

Victor Bocos-Bintintan ◽

Ileana Andreea Ratiu

Keyword(s):

Ion Mobility ◽

Hydrogen Cyanide ◽

Limit Of Detection ◽

Chemical Warfare Agent ◽

Source Model ◽

Negative Ion ◽

Industrial Chemicals ◽

Ionization Source ◽

Toxic Industrial Chemicals ◽

Negative Ion Mode

Sensitive real-time detection of vapors produced by toxic industrial chemicals (TICs) always represents a stringent priority. Hydrogen cyanide (HCN) is definitely a TIC, being widely used in various industries and as an insecticide; it is a reactive, very flammable, and highly toxic compound that affects the central nervous system, cardiovascular system, eyes, nose, throat, and also has systemic effects. Moreover, HCN is considered a blood chemical warfare agent. This study was focused toward quick detection and quantification of HCN in air using time-of-flight ion mobility spectrometry (ToF IMS). Results obtained clearly indicate that IMS can rapidly detect HCN at sub-ppmv levels in air. Ion mobility spectrometric response was obtained in the negative ion mode and presented one single distinct product ion, at reduced ion mobility K0 of 2.38 cm2 V−1 s−1. Our study demonstrated that by using a miniaturized commercial IMS system with nonradioactive ionization source model LCD-3.2E (Smiths Detection Ltd., London, UK), one can easily measure HCN at concentrations of 0.1 ppmv (0.11 mg m−3) in negative ion mode, which is far below the OSHA PEL-TWA value of 10 ppmv. Measurement range was from 0.1 to 10 ppmv and the estimated limit of detection LoD was ca. 20 ppbv (0.02 mg m−3).

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Comprehensive and Rapid Identification of Astilbin Metabolites in Rats Based on Multiple Metabolite Templates Combined with UHPLC-Q-ExactiveMass Spectrometry

Current Drug Metabolism ◽

10.2174/1389200222666210811110619 ◽

2021 ◽

Vol 22 ◽

Author(s):

Shan Jiang ◽

Haoran Li ◽

Ailin Yang ◽

Hongbing Zhang ◽

Pingping Dong ◽

...

Keyword(s):

Mass Spectrometer ◽

Biological Effects ◽

Rat Plasma ◽

Rapid Identification ◽

Negative Ion ◽

Ring Cleavage ◽

Rat Urine ◽

Q Exactive ◽

Negative Ion Mode

Background : Astilbin, a dihydroflavonoid compound widely found in plants, exhibits a variety of pharmacological activities and biological effects. However, little is known about the metabolism of this active compound in vivo, which is very helpful for elucidating the pharmacodynamic material basis and application of astilbin. Objective: To establish a rapid profiling and identification method for metabolites in rat urine, faeces and plasma using a UHPLC-Q-Exactive mass spectrometer in negative ion mode. Methods: In this study, a simple and rapid systematic strategy and 7 metabolite templates, which were established based on previous reports, were utilized to screen and identify astilbin metabolites. Results: As a result, a total of 72 metabolites were detected and characterized, among which 33 metabolites were found in rat urine, while 28 and 38 metabolites were characterized from rat plasma and faeces, respectively. These metabolites were presumed to be generated through ring cleavage, sulfation, dehydrogenation, methylation, hydroxylation, glucuronidation, dehydroxylation and their composite reactions. Conclusion: This study illustrated the capacity of the sensitive UHPLC-Q-Exactive mass spectrometer analytical system combined with the data-mining methods to rapidly elucidate the unknown metabolism. Moreover, the comprehensive metabolism study of astilbin provided an overall metabolic profile, which will be of great help in predicting the in vivo pharmacokinetic profiles and understanding the action mechanism of this active ingredient.

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