Atmospheric pressure desorption-mass

Direct analysis of solid samples or analytes present on solid surfaces without any sample preparation has always been a topic of interest. Desorption electrospray ionization (DESI) is an atmospheric pressure desorption ionization method introduced by Cooks et al., producing ions directly from the surface to be analyzed, which are then sampled with the mass spectrometer [22, 37]. DESI is based on charged liquid droplets that are directed by a high velocity gas jet (in the order of 300 m s ) to the surface to be analyzed. Analytes are desorbed from the surface and analyzed by mass spectrometer (Eig. 1.15). 

Huikko, K., Oestman, P., Sauber, C., Mandel, F., Grigoras, K., Franssila, S., Kotiaho, T., and Kostiainen, R. (2003). Feasibility of atmospheric pressure desorption/ionization on silicon mass spectrometry in analysis of drugs. Rapid Commun. Mass Spectrom. 17 1339-1343. 

From the time of the second edition published in 2001 until now, much progress has been achieved. Several techniques have been improved, others have almost disappeared. New atmospheric pressure desorption ionization sources have been discovered and made available commercially. One completely new instrument, the orbitrap, based on a new mass analyser, has been developed and is now also available commercially. Improved accuracy in low-mass determination, even at low resolution, improvements in sensitivity, better detection limits and more efficient tandem mass spectrometry even on high-molecular-mass compounds are some of the main achievements. We have done our best to include them is this new edition. 

Wei, H. Nolkrantz, K. Powell, D.H. Woods, J.H. Ko, M.-C. Kennedy, R.T. Electrospray Sample Deposition for Matrix-Assisted Laser Desorption/lonization (MALDI) and Atmospheric Pressure MALDI Mass Spectrometry With Attomole Detection Limits, Rapid Commun. Mass Spectrom. 18, 1193-1200 (2004). 

Traditionally, products and adsorbates had to be volatile enough so that they could be carried from the cell into the mass spectrometer, either by headspace sampling, or, more commonly for near-simultaneous analysis (referred to as differential electrochemical mass spectrometry), across a nanoporous, gas-permeable membrane (e.g., Teflon) supported at the tip of a microcapillary placed close to the electrode. Alternatively, a Pt-coated membrane electrode can be used. But the advent of the so-called soft atmospheric pressure desorption/ionization techniques associated with liquid chromatography-mass spectrometry has allowed the sampling of the solvent and involatile solutes directly. The spectra are more... 

Most of the mass spectrometry analyses are conducted under vacuum environment. However, ambient mass spectrometry is a rapidly growing field that provides fast and direct analysis of solid sample surfaces or liquid samples introduced on a suitable surface (Alberici et al. 2010 Weston 2010 Huang et al. 2010 Chen et al. 2010). For that, different ambient ionization MS methods, such as atmospheric pressure desorption/ionization on porous silicon (AP-DIOS) (Huikko et al. 2003), desorption electrospray ionization (DESI) (Takats et al. 2004), direct analysis in real time (DART) (Cody et al. 2005), desorption atmospheric pressure chemical ionization (DAPCI) (Takats et al. 2005), and desorption atmospheric pressure photoionization (DAPPI) (Haapala et al. 2007), have been successfully used in the direct analysis of compounds fi"om various samples, such as body fluids (Cody et al. 2005 Chen et al. 2006), finiits, plant leaves (Luosujarvi et al. 2010), milk (Yang et al. 2009), banknotes (Cody et al. 2005), textiles (Cody et al. 2005 Chen et al. 2007), and pharmaceutical formulations (Ifa et al. 2009 Gheen et al. 2010), just to mention a few, without any sample pretreatment. 

Luosujarvi L, Kanerva S, Saarela V, Franssila S, Kostiainen R, Kotiaho T, Kauppila TJ (2010) Environmental and food analysis by desorption atmospheric pressure photoionization-mass spectrometry. Rapid Commun Mass Spectrom 24 1343-1350 Manicke NE, Kistler T, Ifa DR, Cooks RG, Ouyang Z (2009) High-throughput quantitative analysis by desorption electrospray ionization mass spectrometry. J Am Soc Mass Spectrom 20 321-325 Martynov IL, Karavanskii VA, Kotkovskii GE, Kuzishchin YA, Tsybin AS, Chistyakov AA (2011) Ion mobility spectrometer with ion source based on laser-irradiated porous silicon. Tech Phys Lett 37 15-18... 

Ostman P, Pakaiinen JMH, Vainiotalo P, Franssila S, Kostiainen R, Kotiaho T (2006) Minimum proton affinity for efficient ionization with atmospheric pressure desorption/ionization on silicon mass spectrometry. Rapid Commun Mass Spectrom 20 3669-3673... 

Pihlainen K, Grigoras K, Franssila S, Ketola R, Kotiaho T, Kostiainen R (2005) Analysis of amphetamines and fentanyls by atmospheric pressure desorption/iortization on silicon mass spectrometry and matrix-assisted laser desorption/iortization mass spectrometry and its application to forensic analysis of drug seizures. J Mass Spectrom 40 539-545... 

PDI), the sample is dissolved in a volatile solvent and deposited on a nitrocellulose target material, which is subsequently bombarded with the fission fragments [33-37]. Maity mass spectra of PDl-MS show the occurrence of [M+Na]+ next to [M+H]+ [37], PDl-MS has been extensively used for the analysis of biological macromolecules, but has been superseded by MALDl. Atmospheric-pressure desorption ionization methods are briefly discussed in Sect. 7.2.7. 

This study presents kinetic data obtained with a microreactor set-up both at atmospheric pressure and at high pressures up to 50 bar as a function of temperature and of the partial pressures from which power-law expressions and apparent activation energies are derived. An additional microreactor set-up equipped with a calibrated mass spectrometer was used for the isotopic exchange reaction (DER) N2 + N2 = 2 N2 and the transient kinetic experiments. The transient experiments comprised the temperature-programmed desorption (TPD) of N2 and H2. Furthermore, the interaction of N2 with Ru surfaces was monitored by means of temperature-programmed adsorption (TPA) using a dilute mixture of N2 in He. The kinetic data set is intended to serve as basis for a detailed microkinetic analysis of NH3 synthesis kinetics [10] following the concepts by Dumesic et al. [11]. 

Fast atom bombardment (FAB) Plasma desorption (PD) Liquid secondary-ion mass spectrometry (LSIMS) Thermospray (TSP)/plasmaspray (PSP) Electrohydrodynamic ionisation (EHI) Multiphoton ionisation (MPI) Atmospheric pressure chemical ionisation (APCI) Electrospray ionisation (ESI) Ion spray (ISP) Matrix-assisted laser desorption/ionisation (MALDI) Atmospheric pressure photoionisation (APPI) Triple quadrupole (QQQ) Four sector (EBEB) Hybrid (EBQQ) Hybrid (EB-ToF, Q-ToF) Tandem ToF-ToF Photomultiplier... 

Moyor, S. C. Marzilli, L. A. Woods, A. S. Laiko, V. V. Doroshenko, V. M. Cotter, R. J. Atmospheric pressure matrix-assisted laser desorption/ionization (AP MALDI) on a quadrupole ion trap mass spectrometer. Int. I. Mass Spectrom. 2003, 226,133-150. 

Figure 2.1 Mass spectrometric approach. Dl, direct inlet GC, gas chromatography HPLC, high performance liquid chromatography CZE, capillary zone electrophoresis El, electron ionization Cl, chemical ionization ESI, electrospray ionization DESI, desorption electrospray ionization APCI, atmospheric pressure chemical ionization MALDI, matrix assisted laser desorption ionization B, magnetic analyzer E, electrostatic analyzer...

The ionization techniques described above occur in ion sources that are maintained under high vacuum. In contrast, spray ionization techniques operate at atmospheric pressure a solution spraying from a capillary is ionized at atmospheric pressure and the ions produced are driven into the high vacuum of the mass analyzer where they are separated. The use of spray and desorption ionizations does not require volatilization of the sample before ionization. This means that all these techniques can ionize nonvolatile, polar and large to very large compounds. 

J. M. Wiseman, D. R. Ifa, Q. Song and R. G. Cooks, Tissue imaging at atmospheric pressure using Desorption Electrospray Ionization (DESI) mass spectrometry, Angew. Chem. Int. Edn, 45, 7188 7192 (2006). 

R. D Agata, G. Grasso, S. Parlato, S. Simone, and G. Spoto, The Use of Atmospheric Pressure Laser Desorption Mass Spectrometry for the Study of Iron gall Ink, Appl. Phys. A, 89, 91 95 (2007). 

DGE a AC AMS APCI API AP-MALDI APPI ASAP BIRD c CAD CE CF CF-FAB Cl CID cw CZE Da DAPCI DART DC DE DESI DIOS DTIMS EC ECD El ELDI EM ESI ETD eV f FAB FAIMS FD FI FT FTICR two-dimensional gel electrophoresis atto, 10 18 alternating current accelerator mass spectrometry atmospheric pressure chemical ionization atmospheric pressure ionization atmospheric pressure matrix-assisted laser desorption/ionization atmospheric pressure photoionization atmospheric-pressure solids analysis probe blackbody infrared radiative dissociation centi, 10-2 collision-activated dissociation capillary electrophoresis continuous flow continuous flow fast atom bombardment chemical ionization collision-induced dissociation continuous wave capillary zone electrophoresis dalton desorption atmospheric pressure chemical ionization direct analysis in real time direct current delayed extraction desorption electrospray ionization desorption/ionization on silicon drift tube ion mobility spectrometry electrochromatography electron capture dissociation electron ionization electrospray-assisted laser desorption/ionization electron multiplier electrospray ionization electron transfer dissociation electron volt femto, 1CT15 fast atom bombardment field asymmetric waveform ion mobility spectrometry field desorption field ionization Fourier transform Fourier transform ion cyclotron resonance... 

V. V. Laiko, M. A. Baldwin, and A. L. Burlingame. Atmospheric Pressure Matrix-Assisted Laser Desorption/Ionizarion Mass Spectrometry. Anal. Chem., 72(2000) 652-657. 

Electrospray ionization [21] is one of the most widely utilized ionization techniques employed today for the analysis of thermally fragile molecules. As such, it has assumed an important role in the analysis of biologically important molecules. ESI is a desorption ionization technique. This means that ions are formed before or during the transition from the liquid phase and need not be volatilized in advance of the ionization event (as is the case for El, Cl, etc.). Like APCI and APPI, ESI occurs at atmospheric pressure outside the vacuum chamber of the mass spectrometer (Fig. 11.5). A solution of the analyte passes through... 

Several years later, the next step in the application of MS-MS for mixture analysis was developed by Hunt et al. [3-5] who described a master scheme for the direct analysis of organic compounds in environmental samples using soft chemical ionisation (Cl) to perform product, parent and neutral loss MS-MS experiments for identification [6,7]. The breakthrough in LC-MS was the development of soft ionisation techniques, e.g. desorption ionisation (continuous flow-fast atom bombardment (CF-FAB), secondary ion mass spectrometry (SIMS) or laser desorption (LD)), and nebulisation ionisation techniques such as thermospray ionisation (TSI), and atmospheric pressure ionisation (API) techniques such as atmospheric pressure chemical ionisation (APCI), and electrospray ionisation (ESI). 

Laiko, V.V. Taranenko, N.I. Berkout, V.D. Musselman, B.D. Doroshenko, V.M. Atmospheric Pressure Laser Desorption/Ionization on Porous Silicon. Rapid Commun. Mass Spectrom. 2002,16, 1737-1742. 

Daniel JM, Ehala S, Eriess SD, Zenobi R. 2004. On-line atmospheric pressure matrix-assisted desorption/ionization mass spectrometry. Analyst 129 574. 

Analytes must be liberated from their associated solvent molecules as well as be ionized to allow mass separation. Several ionization methods enable ion production from the condensed phase and have been used for the coupling of CE to MS. Among them, atmospheric pressure ionization (API) methods, matrix-assisted laser desorption/ionization (MALDI), and inductively coupled plasma (ICP) ionization are mainly used. API techniques are undoubtedly the most widespread ionization sources and cover different analyte polarity ranges. 

Fig. 1.33 Schematic plot showing the effect of mass of MgH hydride on the driving force for desorption at 275°C at atmospheric pressure...

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