The Fragmentation of Amine Cluster Ion Including HCl. Proton Affinities of Drugs of Abuse.

Matsumura, Shigeki; Takezawa, Hideyuki

doi:10.5702/massspec.51.196

Cited by 6 publications

(5 citation statements)

References 9 publications

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“…With the compound set and experimental conditions shown in Figure , 10 out of 70 compounds were depleted by 20-fold or greater when using the 2-propanol modifier. However, analytes with higher proton affinities such as leucine (∼917 kJ/mol) and ephedrine (>965 kJ/mol) were not significantly affected by the addition of 2-propanol (∼798 kJ/mol) to the transport gas flow. , For the negative ion mode experimental conditions shown in Figure , 2-propanol did not significantly affect the ion intensities.…”

Section: Resultsmentioning

confidence: 88%

“…However, analytes with higher proton affinities such as leucine (∼917 kJ/mol) and ephedrine (>965 kJ/mol) were not significantly affected by the addition of 2-propanol (∼798 kJ/mol) to the transport gas flow. 18,19 For the negative ion mode experimental conditions shown in Figure 2, 2-propanol did not significantly affect the ion intensities.…”

Section: Figurementioning

confidence: 93%

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Chemical Effects in the Separation Process of a Differential Mobility/Mass Spectrometer System

Schneider¹,

Covey²,

Coy³

et al. 2010

Anal. Chem.

155

200

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In differential mobility spectrometry (DMS, also referred to as high field asymmetric waveform ion mobility spectrometry, FAIMS), ions are separated on the basis of the difference in their mobility under high and low electric fields. The addition of polar modifiers to the gas transporting the ions through a DMS enhances the formation of clusters in a field-dependent way and thus amplifies the high and low field mobility difference resulting in increased peak capacity and separation power. Observations of the increase in mobility field dependence are consistent with a cluster formation model, also referred to as the dynamic cluster-decluster model. The uniqueness of chemical interactions that occur between an ion and cluster-forming neutrals increases the selectivity of the separation and the depression of low-field mobility relative to high-field mobility increases the compensation voltage and peak capacity. The effect of polar modifiers on the peak capacity across a broad range of chemicals has been investigated. We discuss the theoretical underpinnings which explain the observed effects. In contrast to the result from polar modifiers, we find that using mixtures of inert gases as the transport gas improve resolution by reducing peak width but has very little effect on peak capacity or selectivity. Inert gases do not cluster and thus do not reduce low field mobility relative to high-field mobility. The observed changes in the differential mobility α parameter exhibited by different classes of compounds when the transport gas contains polar modifiers or has a significant fraction of inert gas can be explained on the basis of the physical mechanisms involved in the separation processes.

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Section: Resultsmentioning

confidence: 88%

Section: Figurementioning

confidence: 93%

Chemical Effects in the Separation Process of a Differential Mobility/Mass Spectrometer System

Schneider¹,

Covey²,

Coy³

et al. 2010

Anal. Chem.

155

200

View full text Add to dashboard Cite

show abstract

“…The homemade He-DBDI seems as an atmospheric pressure chemical ionization (APCI) because of formation of hydronium ion, H 3 O + , in the positive mode of operation (Habib et al, 2014 , 2020 ). In addition, the proton affinity (PA) of this group of compounds is quite high i.e., PA for MA is 965 kJ/mol, and follows the increasing order: AM < MDA < MA < MDMA (Matsumura et al, 2003 ). Thus, these compounds efficiently form their protonated molecular ion, [M+H] + , in the positive ion mode.…”

Section: Headspace-dielectrictric Barrier Discharge (Dbd) Ionization-mentioning

confidence: 99%

Challenges and Strategies of Chemical Analysis of Drugs of Abuse and Explosives by Mass Spectrometry

Habib

Hong

2021

Front. Chem.

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In analytical science, mass spectrometry (MS) is known as a “gold analytical tool” because of its unique character of providing the direct molecular structural information of the relevant analyte molecules. Therefore, MS technique has widely been used in all branches of chemistry along with in proteomics, metabolomics, genomics, lipidomics, environmental monitoring etc. Mass spectrometry-based methods are very much needed for fast and reliable detection and quantification of drugs of abuse and explosives in order to provide fingerprint information for criminal investigation as well as for public security and safety at public places, respectively. Most of the compounds exist as their neutral form in nature except proteins, peptides, nucleic acids that are in ionic forms intrinsically. In MS, ion source is the heart of the MS that is used for ionizing the electrically neutral molecules. Performance of MS in terms of sensitivity and selectivity depends mainly on the efficiency of the ionization source. Accordingly, much attention has been paid to develop efficient ion sources for a wide range of compounds. Unfortunately, none of the commercial ion sources can be used for ionization of different types of compounds. Moreover, in MS, analyte molecules must be released into the gaseous phase and then ionize by using a suitable ion source for detection/quantification. Under these circumstances, fabrication of new ambient ion source and ultrasonic cutter blade-based non-thermal and thermal desorption methods have been taken into account. In this paper, challenges and strategies of mass spectrometry analysis of the drugs of abuse and explosives through fabrication of ambient ionization sources and new desorption methods for non-volatile compounds have been described. We will focus the literature progress mostly in the last decade and present our views for the future study.

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“…Thus, molecules having high proton affinity were preferentially ionized. Matsumura et al demonstrated the order of the proton affinity of three illicit drugs: amphetamine < methamphetamine (965 kJ/mol) < MDMA . The proton affinity of a tertiary amine is generally higher than that of a primary amine, implying that that of cocaine is higher than that of MDMA.…”

Section: Resultsmentioning

confidence: 99%

“…Matsumura et al demonstrated the order of the proton affinity of three illicit drugs: amphetamine < methamphetamine (965 kJ/mol) < MDMA. 34 The proton affinity of a tertiary amine is generally higher than that of a primary amine, implying that that of cocaine is higher than that of MDMA. The vapor pressure of sample molecules is also an important factor in analyses using the headspace method.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

Development of a Portable Mass Spectrometer Characterized by Discontinuous Sample Gas Introduction, a Low-Pressure Dielectric Barrier Discharge Ionization Source, and a Vacuumed Headspace Technique

et al. 2013

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The present study has attempted to downscale a mass spectrometer in order to make it portable and enable onsite analysis with it. The development of a small mass spectrometer required the use of a compact pump whose displacement was small, decreasing the sensitivity of that spectrometer. To get high sensitivity with a small mass spectrometer, we have integrated novel techniques: a highly sensitive ionization source and efficient extraction of sample vapor. The low-pressure dielectric barrier discharge ionization (LP-DBDI) source made it possible to increase the conductance between the source and the mass analyzer, compared with ambient ionization sources, enhancing the efficiency of the ion transfer from the ionization source to the mass analyzer. We have also developed a vacuumed headspace method efficiently transporting the sample vapor to the ionization source. The sensitivity was further enhanced by also using a discontinuous sample gas introduction technique. A prototype portable mass spectrometer using those novel techniques was found to be sensitive enough to detect 0.1 ppm methamphetamine, 1 ppm amphetamine, 1 ppm 3,4-methylenedioxymethamphetamine, and 10 ppm cocaine in liquid.

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The Fragmentation of Amine Cluster Ion Including HCl. Proton Affinities of Drugs of Abuse.

Cited by 6 publications

References 9 publications

Chemical Effects in the Separation Process of a Differential Mobility/Mass Spectrometer System

Chemical Effects in the Separation Process of a Differential Mobility/Mass Spectrometer System

Challenges and Strategies of Chemical Analysis of Drugs of Abuse and Explosives by Mass Spectrometry

Development of a Portable Mass Spectrometer Characterized by Discontinuous Sample Gas Introduction, a Low-Pressure Dielectric Barrier Discharge Ionization Source, and a Vacuumed Headspace Technique

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