Hquid chromatography mass spectrometry LC-MS

The fundamental components of any modern-day HPLC system are a solvent delivery system, a sample injector, a column, a detector, and a computer with the appropriate data acquisition and processing software. There are numerous HPLC methods described in the literature for isoflavones [13-25] and for the common anthocyanins, each method invokes different combinations of solvent systems, columns, and detectors. HPLC has been interfaced with a variety of detection methods such as ultraviolet/visible (UV/vis) spectrocopy and hquid chromatography-mass spectrometry (LC-MS) [21,22]. In this chapter, however, discussion is restricted to the most commonly used pairing in flavonoid analysis, that of a reverse-phase (RP-18) column and a UV/visible detector. 

Benetti C, Piro R, Binato G, et al.. Simultaneous determination of lincomycin and five macrohde antibiotic residues in honey by hquid chromatography coupled to electrospray ionisation mass spectrometry (LC-MS/MS), Food Addit. Contain. 2006 23(11) 1009-1108. 

Kmellar, B., Abranko, L., Fodor, P, and Lehotay, S. J. 2010. Routine approach to qualitatively screening 300 pesticides and quantification of those frequently detected in fruit and vegetables using hquid chromatography tandem mass spectrometry (LC-MS/MS). FoodAddit. Contam. 27 1415-1430. 

They are all based on detection by hquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) (Boleda et al., 2007 Huerta-Fontela et al., 2007 Postigo et al., 2008b Bijlsma et al., 2009 Gonzdlez-Marino et al., 2009). 

Werner, U. Werner, D. Pahl,A. Mundkowski, R. GUhch, M. Brune, K. Investigation of the pharmacokinetics of celecoxib by hquid chromatography-mass spectrometry, Biomed.ChroTnatogr., 2002,16, 56 60. [LC-MS rofecoxib is internal standard]... 

See footnote cto Table3 LC/PB/MS = hquid chromatography/particle beam mass spectrometry LC/APcl/ESl-MS/MS = liquid chromtography/atmospheric pressure chemical ionization/electrospray ionization tandem mass spectrometry LC/FTIR = Fourier transform infrared LC/TSP-MS/MS = liquid chromatography/thermospray tandem mass spectrometry LC/TSP-MS = liquid chromatography/thermospray mass spectrometry. 

PLE pressurized liquid extraction, LLE liquid-liquid extraction, MAA methacrylic acid, EGDMA ethylene glycol dimethacrylate, HPLC high-performance liquid chromatography, LC hquid chromatography, ESI electrospray ionization, MS mass spectrometry... 

Burton, K.I. Everett, J.R. Newman, MJ. Puhen, F.S. Richards, D.S. Swanson, A.G. On-hne hquid chromatography coupled with high-field NMR and mass spectrometry (LC-NMR-MS) A new technique for drug metahohte structure elucidation. J. Pharm. Biomed. Anal. 1997,15,1903 1912. 

Bianchi, F. et al. Investigation of the separation of heterocyclic aromatic amines by reversed phase ion-pair hquid chromatography coupled with tandem mass spectrometry the role of ion-pair reagents on LC-MS/MS sensitivity. J. Chromatogr. B. 2005, 825, 193-200. 

Sample inlets can also be interfaces that allow the effluents of a variety of powerful separation techniques to enter the ion soimce at a rate that allows for vaporisation to take place. Hence, acronyms such as GC-MS, LC-MS, SFC-MS, etc., relating to gas chromatography, hquid chromatography, supercritical fluid chromatography, etc. coupled to mass spectrometry are now well estabhshed in the jargon of the anal5d ical community as these techniques have been widely accepted and they can be interfaced to any t5q)e of modern mass analyser. 

As a result of the development of special bonded phases, carbohydrates or their derivatives are usually separated by hquid chromatography (LC). However, certain carbohydrate samples are stiU analyzed by gas chromatography (GC) due to the inherent high efficiencies obtainable from the technique and to the associated short elution times. In addition, gas chromatography (GC)/ mass spectrometry (MS) is a particularly powerful analytical technique for carbohydrates, especially for their identification. As a consequence, appropriate derivatives must be formed to render them sufficiently volatile but stiU easily recognizable from their mass spectra. 

---