Easy sonic spray ionization

Desorption electrospray ionization (DESI) [1] was introduced at the end of 2004, and direct analysis in real time (DART) [2] soon after in 2005. The apparent potential of both DESI and DART in high-throughput applications soon led to the development of some derivatives with the intention to broaden the field of applications or to adapt the underlying methodology to specific analytical needs. Now, the repertoire of methods includes variations of the DESI theme such as desorption sonic spray ionization (DeSSI) [3], later renamed easy sonic spray ionization (EASI) [4] or extractive electrospray ionization (EESI) [5,6]. Then, there are the DESI analogs of APCI and APPI, i.e., desorption atmospheric-pressure chemical ionization (DAPCI) [7,8] and desorption atmospheric pressure photoionization (DAPPI) [9]. 

Figure 2,14 Illustration of the V-EASI dual mode of operation (a) V EASI performed for a 30 ng mt sildenaphil solution in acidified methanol and (b) V -EASI performed for a commercial sildenaphil tablet using acidified methanol as the spray solvent [ 104], Reproduced with permission from Santos, VC., Regiani, T., Dias, F.F.C., Romao, W., Jara, J.L.P., Klitzke, C.F., Coelho, F, Eberlins, M.N. (2011) Venturi Easy Ambient Sonic-Spray Ionization. Anal. Chem. 83 1375-1380. Copyright (2011) American Chemical Society...

Santos, V.G., Regiani, T, Dias, F.F.G., Romao, W, Jara, J.L.P., Klitzke, C.F, Coelho, F, Eberlins, M.N. (2011) Venturi Easy Ambient Sonic-Spray Ionization. Anal. Chem. 83 1375-1380. 

Hu, J.-B., Chen, T.-R., Chang, C.-H., Cheng, J.-Y., Chen, Y.-C., Urban, P.L. (2015) A Compact 3D-Printed Interface for Coupling Open Digital Microchips with Venturi Easy Ambient Sonic-Spray Ionization Mass Spectrometry. Analyst 140 1495-1501. 

Cl, chemical Ionization EESI, electrosonic spray Ionization El, electron ionization ICR, ion cyclotron resonance OIT, orbital Ion trap QqQ, triple quadrupole S, seaor SALDI, surface-assisted laser desorptlon/lonizatlon V-EASI, Venturi easy ambient sonic-spray ionization, n.d.. No data. 

In terms of the hardware, TRMS methods described in this book use most common types of ion sources and analyzers. Electrospray ionization (ESI), electron ionization (El), atmospheric pressure chemical ionization (APCI), or photoionization systems, and their modified versions, are all widely used in TRMS measurements. The newly developed atmospheric pressure ionization schemes such as desorption electrospray ionization (DESI) and Venturi easy ambient sonic-spray ionization (V-EASI) have already found applications in this area. Mass analyzers constitute the biggest and the most costly part of MS hardware. Few laboratories can afford purchasing different types of mass spectrometers for use in diverse applications. Therefore, the choice of mass spectrometer for TRMS is not always dictated by the optimum specifications of the instrument but its availability. Fortunately, many real-time measurements can be conducted using different mass analyzers equipped with atmospheric pressure inlets - with better or worse results. For example, triple quadrupole mass spectrometers excel at quantitative capabilities however, in many cases, popular ion trap (IT)-MS instruments can be used instead. On the other hand, applications of TRMS in fundamental studies often require a particular type of instrument (e.g., Fourier transform ion cyclotron resonance mass spectrometer for photodissociation studies on trapped ions). 

EASI easy ambient sonic-spray ionization... 

In 2008, easy ambient sonic-spray ionization mass spectrometry (EASI-MS), originally named desorption sonic spray ionization (DeSSI), was coupled with TLC [69], later with HPTLC [70]. An acidic mixture of methanol and water was sprayed at a maximum flow rate of 15 pL/min coaxial with the supersonic nebulizing gas set at 30 bar. The spray beam of the homemade easy ambient sonic-spray ionization (EASI) source was mounted on the supplied nano-electrospray ionization (nano-ESI) source and directed in a 30-degree angle onto the plate. Without any voltage or heating, just the impact of a high velocity spray served to extract and desorb analytes from the TLC surface and softly ionize them. 

Haddad, R., Milagre, H.M.S., Catharine, R.R., Eberlin, M.N. (2008) Easy ambient sonic-spray ionization mass spectrometry combined with thin-layer chromatography. Analytical Chemistry, 80,2744-2750. 

Eberlin, L.S., Abdelnur, P.V., Passero, A., de Sa, G.F., Daroda, R.J., de Souza, V, Eberlin, M.N. (2009) Analysis of biodiesel and biodiesel-petrodiesel blends by high performance thin layer chromatography combined with easy ambient sonic-spray ionization mass spectrometry. Analyst, 134,1652-1657. 

Chapter 6, titled Selection of Ionization Methods of Analytes in the TLC-MS Techniques provides an overview of mass spectrometric techniques that can be coupled with TLC and act as specific detectors in this hyphenated approach. The mass spectrometric techniques discussed in this chapter are secondary mass spectrometry (SIMS), liquid secondary ion mass spectrometry (LSIMS), fast atom bombardment (FAB), matrix-assisted laser desorption/ionization (MALDI), atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI), electrospray ionization (ESI), desorption electrospray ionization (DESI), electrospry-assisted laser desorption/ionization (ELDI), easy ambient sonic spray ionization (EASI), direct analysis in real time (DART), laser-induced acoustic desorption/electrospray ionization (LIAD/ESI), plasma-assisted multiwavelength laser desorption/ionization (PAMLDI), atmospheric-pressure chemical ionization (APCI), and dielectric barrier discharge ionization (DBDI). For the sake of illustration, the authors introduce practical examples of implementing TLC separations with detection carried out by means of individual mass spectrometric techniques for the systematically arranged compounds belonging to different chemical classes. 

Thin-Layer Chromatography-Easy Ambient Sonic Spray Ionization.95... 

THIN-LAYER CHROMATOGRAPHY-EASY AMBIENT SONIC SPRAY IONIZATION... 

An easy ambient sonic spray ionization (EASI) source uses gentle sonic spray ionization to create charged droplets, which are formed due to the sonic spray causing a statistical imbalance in the distribution of charges. It was used for on-spot detection and analyte characterization on TLC plates. To test its usefulness, an equimolar mixture of three semipolar nitrogenated molecules (allyl phenylamine, phenylamine, and ethylpyridine) was applied to commercial TLC aluminum sheets and resolved... 

Qualitative Thin-Layer Chromatography-Easy Ambient Sonic Spray Ionization Analysis of Seized Cocaine and Crack Cocaine... 292... 

Romao, W., Lalli, P.M., Franco, M.F., Sanvido, G., Schwab, N.V., Lanaro, R., Costa, J.L. et al. 2011. Chemical profile of meta-chlorophenylpiperazine (m-CPP) in ecstasy tablets by easy ambient sonic-spray ionization. X-ray fluorescence, ion mobility mass spectrometry and NMR, Anal. Bioarud. Chem., 400 3053-3064. 

Sabino, B.D., Sodre, M.L., Alves, E.A., Rozembaum, H.F., Alonso, F.O.M, Correa, D.N., Eberlin, M.N., and Romao, W. 2010. Analysis of street Ecstasy tablets by thin layer chromatography coupled to easy ambient sonic-spray ionization mass spectrometry, Braz. J. Anal. Chem., 1 6-11. 

Romao, W., Sabino, B.D., Bueno, M.I.M.S., Vaz, B.G., Junior, A.C., Maldaner, A.O., Castro, E.V.R. et al. 2012. LSD and 9,10-dihydro-LSD Analyses in street drug blotter samples via easy ambient sonic-spray ionization mass spectrometry (EASI-MS), J. 

For ambient mass spectrometric approaches, techniques such as electrospray-assisted pyrolysis ionization (ESA-Py) (Hsu et al., 2005), desorption electrospray ionization (DESl) (Takats et al., 2004), easy ambient sonic-spray ionization (EASl) (Haddad et al., 2008), and atmospheric pressure laser-induced acoustic desorption chemical ionization (AP/LIAD-CI) (Nyadong et al., 2011) have been used for the direct analysis of crude oil with minimal sample pretreatment. Such approaches prevent unexpected effects on the composition of crude oil samples during preparation. Another attractive feature of performing analyses imder ambient conditions is the capacity for rapid sampling, thereby enabhng opportunities for high-throughpnit analysis. 

Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) for crude oil analysis... 

Haddad, R. Sparrapan, R Kotiaho, T. Eberlin, MN. (2008). Easy ambient sonic-spray ionization-membrane interface mass spectrometry for direct analysis of solution constituents. Analytical Chemistry, Vol.80, No.3, pp. 898-903, ISSN 1520-6882. 

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