Time-of-flight quadrupole

Chapter 23 Hybrid Quadrupole Time-of-Flight (Q/TOF) Instruments... 

Q-ToF-LC-MS-MS quadrupole time-of-flight mass analyser in combination with (high performance) liquid chromatography and tandem mass spectrometry... 

Figure 3.10 Schematic of a quadrupole-time-of-flight mass spectrometer. From applications literature published by Micromass UK Ltd, Manchester, UK, and reproduced with permission.

Tandem mass spectrometry (MS-MS) uses more than one mass analyzer for structural and sequencing studies that have been found very useful for anthocyanin characterization. These mass analyzers may be of the same type (triple or quadru-poie)85,86 Qj. such as ion trap quadrupole, - and quadrupole-time-of-flight... 

Currently PCR and mass spectrometry are performed by two separate instruments. However, there is no reason why PCR followed by simple automated cleanup and mass spectrometry cannot be incorporated into a single integrated instrument. Essentially every configuration of the modern ESI mass spectrometer has been used successfully for the analysis of PCR products, from the highest to the lowest resolution involving. Fourier transform ion cyclotron resonance (FTICR), triple quadrupole, quadrupole-time of flight (Q-TOF), and ion trap.22-24 MS discriminates between two structurally related PCR products by MW difference. Mass accuracy is needed to differentiate the... 

Verhaert, P., Uttenweiler-Joseph, S., de Vries, M., Loboda, A., Ens, W., Standing, K.G. (2001). Matrix-assisted laser desorption/ionization quadrupole time-of-flight mass spectrometry an elegant tool for peptidomics. Proteomics 1, 118-131. 

Kuehn, A.V., Neubert, R.H.H. (2004). Characterization of mixtures of alkyl polyglycosides (plantacare). by liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry. Pharm. Res. 21(12), 2347-2353. 

The instrumental analysis for the identification of UV filters degradation products formed during the fungal treatment process was performed by means of HPLC coupled to tandem mass spectrometry using a hybrid quadrupole-time-of-flight mass spectrometer (HPLC-QqTOF-MS/MS). Chromatographic separation was achieved on a Hibar Purospher STAR HR R-18 ec. (50 mm x 2.0 mm, 5 pm, from Merck). In the optimized method, the mobile phase consisted of a mixture of HPLC grade water and acetonitrile, both with 0.15% formic acid. The injection volume was set to 10 pL and the mobile phase flow-rate to 0.3 mL/min. 

Y. Ma, Y. Lu, H. Zeng, D. Ron, W. Mo, T. A. Neubert, Characterization of phosphopeptides from protein digests using matrix assisted laser desorption/ionization time of flight mass spectra metry and nanoelectrospray quadrupole time of flight mass spectrometry, Rapid Commun. Mass Spectrom., 15, 1693 1700 (2001). 

Waridel P, Wolfender J-L, Ndjoko K, Hobby KR, Major HJ and Hostettmann K. 2001. Evaluation of quadrupole time-of-flight tandem mass spectrometry and ion-trap multiple-stage mass spectrometry for the differentiation of C-glycosidic flavonoid isomers. J Chromatogr A 926(1) 29-41. 

Figure 2.11. Schematic of a quadrupole time-of-flight (Qq-TOF) mass spectrometer. Reprinted from A. Westman-Brinkmalm and G. Brinkmalm (2002). In Mass Spectrometry and Hyphenated Techniques in Neuropeptide Research. J. Silberring and R. Ekman (eds.) New York John Wiley Sons, 47-105. With permission of John Wiley Sons, Inc.

In some cases, more than one mass spectrometer may be used to carry out the analysis of a sample. Thus, the components from the first MS analysis may be passed to another MS for further analysis. In this type of analysis, a fragment from the first MS analysis is further broken down and the resulting new fragments are analyzed. This allows for analysis of complex samples. Because there are several types of sample ionization (e.g., El, Cl, and electrospray) and different types of mass spectrometers (e.g., quadrupole, time of flight [TOF], and magnetic sector) there are several different ways an MS-MS analysis can be carried out. 

With the introduction of quadrupole time-of-flight instruments, it became possible to generate fragment spectra with high sensitivity, high... 

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