Linear quadrupole

Martinez Bueno MJM, Agiiera A, Gomez MJ, Hernando MD, Garcia JE, Fernandez-Alba AR (2007) Application of liquid chromatography/quadrupole-linear ion trap mass spectrometry and time-of-flight mass spectrometry to the determination of pharmaceuticals and related contaminants in wastewaters. Anal Chem 79 9372-9384... 

Farre M, Perez S, Gajda-Schrantz K, Osorio V, Kantiani L, Ginebreda A, Barcelo D (2010) First determination of C60 and C70 fullerenes and N-methylfulleropyrrolidine C60 on the suspended material of wastewater effluents by liquid chromatography hybrid quadrupole linear ion trap tandem mass spectrometry. J Hydrol 383(l-2) 44-51... 

Jelic A, Petrovic M, Barcelo D (2009) Multi-residue method for trace level determination of pharmaceuticals in solid samples using pressurized liquid extraction followed by liquid chromatography/quadrupole-linear ion trap mass spectrometry. Talanta 80 363-371... 

QqLIT-MS-MS Quadrupole linear ion trap tandem mass spectrometer... 

Mass spectrometric analysis was performed with a hybrid triple quadrupole/ linear ion trap Applied Biosystem MSD Sciex 4000QTRAP (Applied Biosystems, Foster City, USA) instrument equipped with a Turbospray ESI interface. For target quantitative analyses, data acquisition was performed in SRM, recording the transitions between the precursor ion and the two most abundant fragment ions. The developed instrumental method display excellent LODs in SRM mode between 0.5 and 1.2 pg (Table 2). 

QqLIT Triple quadrupole-linear ion trap mass analyzer... 

Guerra P, Eljarrat E, Barcelo D (2008) Enantiomeric specific determination of hexabromo-cyclododecane by liquid chromatography-quadrupole linear ion trap mass spectrometry in sediment samples. J Chromatogr A 1203 81-87... 

Fig. 1.24 Schematic of the triple quadrupole linear ion trap (AB/MDS Sciex). Q3 can be operated in quadrupole or trap mode. In both modes ions are detected in the axial direction.

In the triple quadrupole linear ion trap, tandem MS is performed in space where the LIT serves only as a trapping and mass-analyzing device. Figure 1.25 illustrates the difference between quadrupole CID spectra and trap CID spectra for trocade. 

Table 1.4 Mode of operation of the triple quadrupole linear ion trap (QqQLir).

Fig. 1.39 LC-MS data dependent analysis of vinpocetin in rat urine using dynamic background substraction (DBS) on a triple quadrupole linear ion trap. (A) Full scan MS (survey scan) trace. (B) Enhanced product ion scan (dependent scan). The major peak at 3.9 min corresponds to apovinpocetin, the minor one at 2.9 min to the hydroxylation product of apovinpocetin (m/z 339).

Hopfgartner, G. Varesio, E. Tschappat, V. Grivet, C. Emmanuel Bourgogne, E. Leuthold, L. A. Triple quadrupole linear ion trap mass spectrometer for the analysis of small molecules and macromolecules. J. Mass Spectrom. 2004, 39, 845-855. 

Hopfgartner, G. Husser, C. Zell, M. Rapid screening and characterization of drug metabolites using a new quadrupole-linear ion trap mass spectrometer. J Mass Spectrom 2003, 38, 138-150. 

Since the analytical point of view most of current analytical methods are based on LC-MS/MS, but for some classes of pesticides GC-MS continues being the technique of choice. The use of quadrupole ion trap (QIT) to analyze multiple pesticide residues is limited to several multiclass pesticides in fruit [162], because of the limited number of ions that can be isolated at the same time. For this reason, the use of several time windows is required and this is indeed a strong limitation in practice. The use of hybrid triple quadrupole linear ion trap (QqLlT) mass spectrometer has provided significant contribution to the development of high-sensitive multiresidue analytical methods for pesticide control. An example of application is the method reported by Hernando et al. for the analysis of pesticide residues in olive oil [65]. 

A new generation of linear ion trap mass spectrometers has been developed and exhibits increased performance compared to traditional three-dimensional (3D) ion traps (Hopfgartner et al., 2003 Douglas et al., 2005). A further evolution of the triple-quadrupole family and ion trap class of instruments is the production of the hybrid triple-quadrupole/linear ion trap (QQQ/LIT) platform. Hybrid instruments of this nature allow for operation in space and not just in time when performing MS/MS analysis. This feature allows for increased performance compared to classical ion traps. A powerful combination possible on a hybrid LIT/QQQ instrument is the ability to use highly sensitive and selective precursor ion, constant neutral loss, and multi-MRM as a survey scan for dependent LIT MS/MS. Compared to a simple MS experiment, these comprehensive triple-quadrupole and LIT modes can be more complex to setup. 

Hager, J. W., and Le Blanc, J. C. (2003). High-performance liquid chromatography-tandem mass spectrometry with a new quadrupole/linear ion trap instrument. J. Chromatogr. A 1020 3-9. 

Li, A. C., Gohdes, M. A., and Shou, W. Z. (2007). N-in-one strategy for metabolite identification using a liquid chromatography/hybrid triple quadrupole linear ion trap instrument using multiple dependent product ion scans triggered with full mass scan. Rapid Commun. Mass Spectrom. 21 1421-1430. 

Zhang, M. Y., Pace, N., Kerns, E. H., Kleintop, T., Kagan, N., and Sakuma, T. (2005). Hybrid triple quadrupole-linear ion trap mass spectrometry in fragmentation mechanism studies Application to structure elucidation of buspirone and one of its metabolites. J. Mass. Spectrom. 40 1017-1029. 

Williamson, B. L., Marchese, J., and Morrice, N. A. (2006). Automated identification and quantification of protein phosphorylation sites by LC/MS on a hybrid triple quadrupole linear ion trap mass spectrometer. Mol. Cell. Proteomics 5 337-346. 

Thomas, A., Hopfgartner, G., Giroud, C., and Staub, C. (2009). Quantitative and qualitative profiling of endocannabinoids in human plasma using a triple quadrupole linear ion trap mass spectrometer with liquid chromatography. Rapid Commun. Mass Spectrom. 23, 629—638. 

Among these, both LC-MS and LC-MS/MS approaches have been described using different mass analyzers operating in the positive ion mode scan such as triple stage quadrupole (TSQ) mass spectrometers [145, 194, 226, 227, 235, 239, 240, 242-247] and hybrid quadrupole-linear ion trap (LTQ) [173, 193, 218, 238, 241] mass spectrometers working in SRM mode as well as time-of-flight (TOF) [195] and hybrid quadrupole-TOF (Q-TOF) [236,237] mass spectrometers working in the MS mode. 

Taylor K, Elliott S (2009) A validated hybrid quadrupole linear ion-trap LC-MS method for the analysis of morphine and morphine glucuronides applied to opiate deaths. Forensic Sci Int 187(l-3) 34 fl. doi S0379-0738(09)00085-l [pii] 10.1016/j.forsciint.2009.02.011... 

Marquet, P., Saint-Marcoux, F., Gamble, T.N., Leblanc, J.C. (2003). Comparison of a preliminary procedure for the general unknown screening of drugs and toxic compounds using a quadrupole-linear ion-trap mass spectrometer with a liquid chromatography-mass spectrometry reference technique. J. Chromatogr. B Anal. Technol. Biomed. Life Sci. 789(1) 9-18. 

Prefractionation of proteins in an Arabidopsis thalicma leaf extract by means of fast-performance LC prior to SCXxRPLC-MS on a monolithic RPLC column allowed the identification of 1032 unique proteins in 4 mg of a protein plant leaf tissue extract [59]. Fractionation of human plasma proteins by on-line SCX and RPLC was performed prior to tryptic digestion [60]. The resulting 30 fractions were digested and analysed by LC-MS on a quadrupole-linear-ion-trap (Q-LIT) instmment. Using this approach, 1292 proteins were identified, some of which are know to be present at <10 ng/ml. 

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