Atmospheric-pressure chemical ionization and mass

The term nebulizer is used generally as a description for any spraying device, such as the hair spray mentioned above. It is normally applied to any means of forming an aerosol spray in which a volume of liquid is broken into a mist of vapor and small droplets and possibly even solid matter. There is a variety of nebulizer designs for transporting a solution of analyte in droplet form to a plasma torch in ICP/MS and to the inlet/ionization sources used in electrospray and mass spectrometry (ES/MS) and atmospheric-pressure chemical ionization and mass spectrometry (APCI/MS). 

An on-line chromatography/atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCI/MS/MS) methods was developed for rapid screen of pharmacokinetics of different drugs, including 5 (98RCM1216). The electron impact mass spectrum of 5 and ethyl 9,10-difluoro-3-methyl-7-oxo-2,3-dihydro-7Ff-pyrido[l,2,3- fe]-l,4-benzoxazine-6-carboxylate was reported (97MI28). Electron impact/Fourier transform... 

D. Puig, L. Silgoner, M. Grasserbauer and D. Barcelo, Part-per-trillion level determination of priority methyl-, nirto-, and clilor ophenols in river water samples by automated online liquid/solid exrtaction followed by liquid chr omatography/mass spectr ometry using atmospheric pressure chemical ionization and ion spray interfaces . Anal. Chem. 69 2756-2761 (1997). 

Van Breemen, R.B. et al.. Liquid chromatography/mass spectrometry of carotenoids using atmospheric pressure chemical ionization, J. Mass Spectrom., 31, 975, 1996. Tian, Q., Duncan C.J.G., and Schwartz S. J., Atmospheric pressure chemical ionization mass spectrometry and in-source fragmentation of lutein esters, J. Mass Spectrom., 38, 990, 2003. 

Homish, R. E. and Wiest, J. R., Quantitation of spectinomycin residues in bovine tissues by ion-exchange high-performance liquid chromatography with post-column derivatization and confirmation by reversed-phase high performance chromatography-atmospheric pressure chemical ionization tandem mass spectrometry, /. Chromatogr. A, 812, 123, 1998. 

G. A. van der Doelen, K. J. van den Berg, J. J. Boon, N. Shibayama, E. R. de la Rie, W. J. L. Genuit, Analysis of fresh triterpenoid resins and aged triterpenoid varnishes by high performance liquid chromatography atmospheric pressure chemical ionization (tandem) mass spectrometry, J. Chromatogr., A, 809, 21 37 (1998). 

Bourgogne E., Grivet C., and Hopfgartner G., 2005. Determination of talinolol in human plasma using automated online solid phase extraction combined with atmospheric pressure chemical ionization tandem mass spectrometry. J Chromatogr B 820 103. 

L. Di Donna, L. Maiuolo, F. Mazzotti, D. De Luca and G. Sindona, Assay of Sudan I contamination of foodstuffs by atmospheric pressure chemical ionization tandem mass spectrometry and isotope dilution. Anal. Chem., 76 (2004) 5104-5108. 

Gardner DR, Panter KE, Pfister JA, Knight AP. 1999. Analysis of toxic norditerpenoid alkaloids in Delphinium species by electrospray, atmospheric pressure chemical ionization, and sequential tandem mass spectrometry. J Agric Food Chem 47 5049. 

Karlsson AA, Michelsen P, Odham G. 1998. Molecular species of sphingomyelin determination by high-performance liquid chromatography/mass spectrometry with electrospray and high-performance liquid chromatography/tandem mass spectrometry with atmospheric pressure chemical ionization. J Mass Spectrom 33 1192. 

Kratzsch C, Peters FT, Kraemer T, Weber AA, Maurer HH. 2003. Screening, library-assisted identification and validated quantification of fifteen neuroleptics and three of their metabolites in plasma by liquid chromatography/ mass spectrometry with atmospheric pressure chemical ionization. J Mass Spectrom 38 283. 

Moody DR, Laycock JD, Huang W, Foltz RL. 2004. A high-performance liquid chromatographic-atmospheric pressure chemical ionization-tandem mass spectrometric method for determination of risperidone and 9-hydroxyr-isperidone in human plasma. J Anal Toxicol 28 494. 

Rauha, J. P., Vuorela, H., and Kostiainen, R. (2001). Effect of eluent on the ionization efficiency of flavonoids by ion spray, atmospheric pressure chemical ionization, and atmospheric pressure photoionization mass spectrometry.. Mass Spectrom. 36, 1269—1280. 

X. Xu, A.M. van der Craats, E.M. Kok and P.C.A.M. de Bruyn, Trace analysis of peroxide explosives by high performance liquid chromatography — atmospheric pressure chemical ionization — tandem mass spectrometry (HPLC-APCl-MS/MS) for forensic applications ,... 

Liang, H.R. Foltz, R.L. Meng, M. Bennett, P. Ionization enhancement in atmospheric pressure chemical ionization and suppression in electrospray ionization between target drugs and stable-isotope-labeled internal standards in quantitative liquid chromatography/tandem mass spectrometry. Rapid Commun. Mass Spectrom. 2003, 17, 2815—2821. 

C. Nomeir, A. A. Validation of higher-throughput high-performance liquid chromatography/atmospheric pressure chemical ionization tandem mass spectrometry assays to conduct cytochrome P450s CYP2D6 and CYP3A4 enzyme inhibition studies in human liver microsomes. Rapid Commun Mass Spectrom 2000, 14, 207-214. 

De Rijke, E. et al.. Liquid chromatography with atmospheric pressure chemical ionization and electrospray ionization mass spectrometry of flavonoids with triple-quadrupole and ion-trap instruments, J. Chromatogr. A, 984, 45, 2003. 

Manners GD, Breksa AP III, Schoch TK, Hidalgo MB. Analysis of bitter limonoids in citrus juices by atmospheric pressure chemical ionization and electrospray ionization liquid chromatography-mass spectrometry. J Agric Food Chem 2003 51(13) 3709-3714. 

Cristoni S, Cuccato D, Sciannamblo M, Bernardi LR, Biunno I, Gerthoux P, Russo G, Weber G, Mora S (2004) Analysis of 21 deoxycortisol, a marker of congenital adrenal hyperplasia, in blood by atmospheric pressure chemical ionization and electrospray ionization using multiple reaction monitoring. Rapid Commun Mass Spectrom 18 77-82... 

C Aguilar, I Ferrer, F Borrull, RM Marce, D Barcelo. Comparison of automated on-line solid-phase extraction followed by liquid chromatography mass spectrometry with atmospheric pressure chemical ionization and particle beam mass spectrometry for the determination of a priority group of pesticides in environmental waters. J Chromatogr A 794 147-163, 1998. 

Lien G, Chen C, Wang G (2009) Comparison of electrospray ionization, atmospheric pressure chemical ionization and atmospheric pressure photoionization for determining estrogenic chemicals in water by liquid chromatography tandem mass spectrometry with chemical derivatizations. J Chromatogr A 1216 956-966... 

Application of LC-MS/MS techniques to the analysis of phthalate ester metabolites in urine have also been developed. For example, Blount et al. (2000b) have developed an assay to quantify the monoester metabolites (including MEHP) of eight phthalate diesters in urine, utilizing HPLC coupled with atmospheric pressure chemical ionization and tandem mass spectrometric (APCI-MS/MS) detection techniques. Urine samples were treated with -glucuronidase to release the free phthalate monoesters followed by a two-step solid phase extraction procedure. After evaporative concentration of the eluant, the analytes in the purified samples are further separated on a phenyl reverse phase HPLC column and quantified by APCI-MS/MS, following careful optizimation of the APCI-MS/MS instrument. The limits of detection for MEHP were determined to be 1.2 ng/ml urine with recovery efficiencies of between 78 and 91%. 

A number of recent investigations have shown that mass spectrometry (MS) is a rapid and effective method for the identification of triacylglycerol species of milk fat that are compositionally different (Myher et al., 1988, 1993 Laakso and Kallio, 1993 Spanos et al., 1995 Laakso and Manninen, 1997 Mottram and Evershed, 2001 Kalo et al., 2004). In fact, a range of mass spectral techniques, such as electron ionization, fast atom bombardment, chemical ionization, atmospheric pressure chemical ionization and electrospray MS, have been used to study triacylglycerols. The later three are soft ionizing techniques, which retain substantial amounts of the molecular ion, rather than fragmenting the molecule into a number of parts. These methods have allowed the determination of... 

Simultaneous Quantification of Flunitrazepam (Rohypnol) and its Major Metabolites in Human Plasma by Solid Phase Extraction and High-Performance Liquid Chromatography Atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry, Using Deuterium Labeled Flunitrazepam as Internal Standard... 

These direct ion sources exist under two types liquid-phase ion sources and solid-state ion sources. In liquid-phase ion sources the analyte is in solution. This solution is introduced, by nebulization, as droplets into the source where ions are produced at atmospheric pressure and focused into the mass spectrometer through some vacuum pumping stages. Electrospray, atmospheric pressure chemical ionization and atmospheric pressure photoionization sources correspond to this type. In solid-state ion sources, the analyte is in an involatile deposit. It is obtained by various preparation methods which frequently involve the introduction of a matrix that can be either a solid or a viscous fluid. This deposit is then irradiated by energetic particles or photons that desorb ions near the surface of the deposit. These ions can be extracted by an electric field and focused towards the analyser. Matrix-assisted laser desorption, secondary ion mass spectrometry, plasma desorption and field desorption sources all use this strategy to produce ions. Fast atom bombardment uses an involatile liquid matrix. 

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