Liquid chromatograph—mass spectrometer—computer analytical systems

Horning, E. C.; Carroll, D. I.; Džidić, I.; Haegele, K. D.; Horning, M. G.; Stillwell, Richard

doi:10.1016/s0021-9673(00)90841-0

Cited by 192 publications

(96 citation statements)

References 3 publications

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“…For instance, for two of the reagent ions used in this study, NO − 3 and Na + , the ion-molecule reaction time (i.e., ion drift time) in the IMR is estimated to be 0.5-1 and 0.4-0.7 ms, respectively, with an ion mobility of 2.37 cm 2 s −1 V −1 for NO − 3 (Ellis et al, 1978) and 3.4 cm 2 s −1 V −1 for Na + (Bohringer et al, 1987) under typical operation conditions (2-4 kV across the IMR). However, when using electrospray as a source and sampling ambient air of different humidity, the reagent ions can be solvated by methanol or water clusters (Horning et al, 1974;Garvey et al, 1994). As the ion mobility of solvated reagent ions is likely smaller than that for un-solvated reagent ions, the ion-molecule reaction time between solvated reagent ions and gas-phase analytes in the IMR is expected to be longer than that estimated for the un-solvated ions.…”

Section: Instrument Descriptionmentioning

confidence: 99%

An electrospray chemical ionization source for real-time measurement of atmospheric organic and inorganic vapors

et al. 2017

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Abstract. We present an electrospray ion source coupled to an orthogonal continuous-flow atmospheric pressure chemical ionization region. The source can generate intense and stable currents of several specific reagent ions using a range of salt solutions prepared in methanol, thereby providing both an alternative to more common radioactive ion sources and allowing for the generation of reagent ions that are not available in current chemical ionization mass spectrometry (CIMS) techniques, such as alkaline cations. We couple the orthogonal electrospray chemical ionization (ESCI) source to a high-resolution time-of-flight mass spectrometer (HRToF-MS), and assess instrument performance through calibrations using nitric acid (HNO 3 ), formic acid (HCOOH), and isoprene epoxydiol (trans-β-IEPOX) gas standards, and through measurements of oxidized organic compounds formed from ozonolysis of α-pinene in a continuous-flow reaction chamber. When using iodide as the reagent ion, the HR-ToF-ESCIMS prototype has a sensitivity of 11, 2.4, and 10 cps pptv −1 per million counts per second (cps) of reagent ions and a detection limit (3σ , 5 s averaging) of 4.9, 12.5, and 1.4 pptv to HNO 3 , HCOOH, and IEPOX, respectively. These values are comparable to those obtained using an iodide-adduct HR-ToF-CIMS with a radioactive ion source and low-pressure ion-molecule reaction region. Applications to the α-pinene ozonolysis system demonstrates that HRToF-ESCIMS can generate multiple reagent ions (e.g., I − , NO − 3 , acetate, Li + , Na + , K + , and NH + 4 ) having different selectivity to provide a comprehensive molecular description of a complex organic system.

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Section: Instrument Descriptionmentioning

confidence: 99%

An electrospray chemical ionization source for real-time measurement of atmospheric organic and inorganic vapors

et al. 2017

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“…The same experiments were also performed on a 3,7-dimethoxykaempferol derivative (7). In this case also a facile loss of CH 3 .…”

Section: (317 -> 302) (Cid 35 %) D) Q-tof-ms/ms (20 Ev) E) Q-tof-ms/mmentioning

confidence: 99%

“…Electrospray (ES) [6] or Atmospheric Pressure Chemical Ionisation (APCI) [7], are soft ionisation techniques which generate mainly molecular ions for relatively small plant metabolites such as flavonoids. Molecular weight information alone is however not sufficient for the on-line structure determination of natural products and fragment information is necessary for partial on-line identification or for dereplication of known constituents.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of Q-TOF-MS/MS and multiple stage IT-MSⁿ for the dereplication of flavonoids and related compounds in crude plant extracts

Wolfender¹,

Waridel²,

Ndjoko³

et al. 2000

Analusis

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“…Moreover, the detection limits of the methods that have been proposed are of use only in the range 80-100 ppb in the best cases, which is well above the required limit for thiourea. A very fast method, developed for the direct determination of thiourea in waste water by tandem mass spectrometry 9 with atmospheric pressure chemical ionisation (APCI) 10 and selected-reaction monitoring will be described here. It requires minimal pretreatment of the sample and the time of analysis, based on flow injection analysis (FIA), is less than 1 min/ sample.…”

mentioning

confidence: 99%

Rapid Determination of Thiourea in Waste Water by Atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry Using Selected‐reaction Monitoring

Raffaelli

Pucci

Lazzaroni

et al. 1997

Rapid Commun. Mass Spectrom.

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Thiourea, a toxic substance for nitrification bacteria, active at low concentration levels (toxicity limit: 76 ppb), cannot be analysed by conventional methods. Its high solubility in water and insolubility in non-polar organic solvents, such as diethyl ether or dichloromethane, make its extraction impossible. A rapid method for the direct determination of thiourea in waste water with a minimal sample pre-treatment by atmospheric-pressure chemical ionisation mass spectrometry is presented here. The method takes advantage of tandem mass spectrometry with selected-reaction monitoring so that the system acts as a completely specific detector for thiourea, A detection limit of 1 ppb has been obtained and linear calibration has been determined in the concentration range 10-5000 ppb. The reliability of the method was tested by the analysis of spiked samples, showing good accuracy. The method also proved its ruggedness in the analysis of real samples, giving very good results, despite the complexity of the matrix.

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Liquid chromatograph—mass spectrometer—computer analytical systems

Cited by 192 publications

References 3 publications

An electrospray chemical ionization source for real-time measurement of atmospheric organic and inorganic vapors

An electrospray chemical ionization source for real-time measurement of atmospheric organic and inorganic vapors

Evaluation of Q-TOF-MS/MS and multiple stage IT-MSⁿ for the dereplication of flavonoids and related compounds in crude plant extracts

Rapid Determination of Thiourea in Waste Water by Atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry Using Selected‐reaction Monitoring

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Liquid chromatograph—mass spectrometer—computer analytical systems

Cited by 192 publications

References 3 publications

An electrospray chemical ionization source for real-time measurement of atmospheric organic and inorganic vapors

An electrospray chemical ionization source for real-time measurement of atmospheric organic and inorganic vapors

Evaluation of Q-TOF-MS/MS and multiple stage IT-MSn for the dereplication of flavonoids and related compounds in crude plant extracts

Rapid Determination of Thiourea in Waste Water by Atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry Using Selected‐reaction Monitoring

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Product

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Evaluation of Q-TOF-MS/MS and multiple stage IT-MSⁿ for the dereplication of flavonoids and related compounds in crude plant extracts