Editing Ion source (section)

===Sonic spray ionization===

Sonic spray ionization is  method for creating ions from a liquid solution, for example, a mixture of methanol and water.<ref name="pmid8779414">{{cite journal |vauthors=Hirabayashi A, Sakairi M, Koizumi H |title=Sonic spray mass spectrometry |journal=Anal. Chem. |volume=67 |issue=17 |pages=2878–82 |date=1995 |pmid=8779414|doi=10.1021/ac00113a023}}</ref> A [[pneumatic]] nebulizer is used to turn the solution into a  [[supersonic]] spray of small droplets. Ions are formed when the solvent evaporates and the statistically unbalanced charge distribution on the droplets leads to a net charge and complete desolvation results in the formation of ions. Sonic spray ionization is used to analyze small organic molecules and drugs and can analyze large  molecules when an electric field is applied to the capillary to help increase the charge density and generate multiple charged ions of proteins.<ref>{{Cite journal|last1=Chen|first1=Tsung-Yi|last2=Lin|first2=Jia-Yi|last3=Chen|first3=Jen-Yi|last4=Chen|first4=Yu-Chie|date=2011-11-22|title=Ultrasonication-assisted spray ionization mass spectrometry for the analysis of biomolecules in solution|journal=Journal of the American Society for Mass Spectrometry|language=en|volume=21|issue=9|pages=1547–1553|doi=10.1016/j.jasms.2010.04.021|pmid=20547459|issn=1044-0305|doi-access=free|bibcode=2010JASMS..21.1547C }}</ref>

Sonic spray ionization has been coupled with [[high performance liquid chromatography]] for the analysis of drugs.<ref name="pmid11908800">{{cite journal |vauthors=Arinobu T, Hattori H, Seno H, Ishii A, Suzuki O |title=Comparison of SSI with APCI as an interface of HPLC-mass spectrometry for analysis of a drug and its metabolites |journal=J. Am. Soc. Mass Spectrom. |volume=13 |issue=3 |pages=204–208 |date=2002 |pmid=11908800 |doi=10.1016/S1044-0305(01)00359-2|doi-access=free |bibcode=2002JASMS..13..204A }}</ref><ref name="pmid12141684">{{cite journal |vauthors=Dams R, Benijts T, Günther W, Lambert W, De Leenheer A |title=Sonic spray ionization technology: performance study and application to a LC/MS analysis on a monolithic silica column for heroin impurity profiling |journal=Anal. Chem. |volume=74 |issue=13 |pages=3206–3212 |date=2002 |pmid=12141684 |doi=10.1021/ac0112824}}</ref> Oligonucleotides have been studied with this method.<ref name="pmid11990592">{{cite journal |vauthors=Huang M, Hirabayashi A, Okumura A, Hirabayashi Y |title=Matrix effect on the analysis of oligonucleotides by using a mass spectrometer with a sonic spray ionization source |journal=Anal Sci |volume=17 |issue=10 |pages=1179–1182 |date=2001 |pmid=11990592 |doi=10.2116/analsci.17.1179|doi-access=free }}</ref><ref name="pmid11999509">{{cite journal |vauthors=Huang M, Hirabayashi A |title=Multi-charged oligonucleotide ion formation in sonic spray ionization |journal=Anal Sci |volume=18 |issue=4 |pages=385–390 |date=2002 |pmid=11999509 |doi=10.2116/analsci.18.385|doi-access=free }}</ref> SSI has been used in a manner similar to desorption electrospray ionization<ref name="pmid16941547">{{cite journal |vauthors=Haddad R, Sparrapan R, Eberlin MN |title=Desorption sonic spray ionization for (high) voltage-free ambient mass spectrometry |journal=Rapid Commun. Mass Spectrom. |volume=20 |issue=19 |pages=2901–2905 |date=2006 |pmid=16941547 |doi=10.1002/rcm.2680|bibcode=2006RCMS...20.2901H }}</ref> for [[ambient ionization]] and has been coupled with [[thin-layer chromatography]] in this manner.<ref name="pmid18331004">{{cite journal |vauthors=Haddad R, Milagre HM, Catharino RR, Eberlin MN |title=Easy Ambient Sonic-Spray Ionization Mass Spectrometry Combined with Thin-Layer Chromatography |journal=Anal. Chem. |volume= 80|issue= 8|pages= 2744–2750|date=2008 |pmid=18331004 |doi=10.1021/ac702216q}}</ref>