{"id":135,"date":"2019-07-26T15:25:52","date_gmt":"2019-07-26T19:25:52","guid":{"rendered":"https:\/\/sites.temple.edu\/levislab\/?page_id=135"},"modified":"2021-03-26T09:46:19","modified_gmt":"2021-03-26T13:46:19","slug":"laser-electrospray-mass-spectrometry","status":"publish","type":"page","link":"https:\/\/sites.temple.edu\/levislab\/laser-electrospray-mass-spectrometry\/","title":{"rendered":"Laser Electrospray Mass Spectrometry"},"content":{"rendered":"\n<div class=\"wp-block-media-text alignwide is-stacked-on-mobile\" style=\"grid-template-columns:40% auto\"><figure class=\"wp-block-media-text__media\"><img loading=\"lazy\" decoding=\"async\" width=\"670\" height=\"543\" src=\"https:\/\/sites.temple.edu\/levislab\/files\/2019\/07\/LEMSbutton-e1564169226150.jpg\" alt=\"\" class=\"wp-image-133 size-full\" srcset=\"https:\/\/sites.temple.edu\/levislab\/files\/2019\/07\/LEMSbutton-e1564169226150.jpg 670w, https:\/\/sites.temple.edu\/levislab\/files\/2019\/07\/LEMSbutton-e1564169226150-300x243.jpg 300w\" sizes=\"auto, (max-width: 670px) 100vw, 670px\" \/><\/figure><div class=\"wp-block-media-text__content\">\n<p>The objective of our research is to develop a new type of ambient mass spectrometric technique combining non-resonant fs laser vaporization and electrospray ionization. The two methods combined allows for the vaporization of neutral sample molecules using the nonresonant fs laser and post-ionization using the electrospray. Using laser electrospray mass spectrometry (LEMS) we have successfully analyzed explosives, pharmaceuticals, large biomolecules and tissue.<\/p>\n<\/div><\/div>\n\n\n\n<div style=\"height:50px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p><strong>Ambient Mass Spectrometry of Neutral Samples:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>LEMS combines non-resonant femtosecond laser vaporization and electrospray post-ionization.<\/li><li>Neutral molecules are vaporized from a sample surface using a femtosecond laser.<\/li><li>The neutral molecules are captured in the electrospray plume, where they undergo ionization.<\/li><li>The ions travel to the inlet of the mass spectrometer for detection and mass analysis.<\/li><\/ul>\n\n\n\n<div style=\"height:50px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-text-align-center\"><strong>LEMS of Vitamin B12<\/strong><\/p>\n\n\n\n<div class=\"wp-block-media-text alignwide is-stacked-on-mobile\"><figure class=\"wp-block-media-text__media\"><img loading=\"lazy\" decoding=\"async\" width=\"480\" height=\"375\" src=\"https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/matrixfree_B12.jpg\" alt=\"\" class=\"wp-image-211 size-full\" srcset=\"https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/matrixfree_B12.jpg 480w, https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/matrixfree_B12-300x234.jpg 300w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><\/figure><div class=\"wp-block-media-text__content\">\n<p>A 250 mL aliquot of 10<sup>-3<\/sup> M vitamin B12 was spotted and dried on a glass slide and analyzed using LEMS. The acquired mass spectrum shows the protonated molecular ion at&nbsp;<em>m\/z<\/em> 1356. The doubly charged ion is also observed demonstrating that electrospray ionization is the dominante mechanism. This is the first demonstration of matrix-free vaporization of neutral molecules at atmospheric conditions with a nonresonant femtosecond laser.<\/p>\n<\/div><\/div>\n\n\n\n<div style=\"height:50px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-text-align-center\"><strong>LEMS of Human Blood<\/strong><\/p>\n\n\n\n<div class=\"wp-block-media-text alignwide has-media-on-the-right is-stacked-on-mobile\"><figure class=\"wp-block-media-text__media\"><img loading=\"lazy\" decoding=\"async\" width=\"480\" height=\"374\" src=\"https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/wet_blood-2.jpg\" alt=\"\" class=\"wp-image-229 size-full\" srcset=\"https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/wet_blood-2.jpg 480w, https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/wet_blood-2-300x234.jpg 300w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><\/figure><div class=\"wp-block-media-text__content\">\n<p>Human blood deposited on a metal  slide was subjected to LEMS analysis. Multiple charging of hemoglobin subunits (a and b hemoglobin subunits are denoted by the squares and circles, respectively) indicates electrospray ionization is the dominant mechanism. In addition to the a and b hemoglobin subunits, the b heme is also present in the mass spectrum. We have  demonstrated, using femtosecond laser pulses, that the vaporization of intact  molecules up to 16,000 Da  under ambient conditions is possible.<\/p>\n<\/div><\/div>\n\n\n\n<div style=\"height:50px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-text-align-center\"><strong>Mass Spectral Imaging using LEMS<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"830\" height=\"323\" src=\"https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/oxy_image.jpg\" alt=\"\" class=\"wp-image-234\" srcset=\"https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/oxy_image.jpg 830w, https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/oxy_image-300x117.jpg 300w, https:\/\/sites.temple.edu\/levislab\/files\/2019\/08\/oxy_image-768x299.jpg 768w\" sizes=\"auto, (max-width: 830px) 100vw, 830px\" \/><\/figure>\n\n\n\n<p>A 50 mL aliquot of 10<sup>-5<\/sup> M oxycodone was spotted and dried on a stainless steel slide and analyzed using LEMS. A typical mass spectrum from red spots on the reconstructed image shows protonated adduct of oxycodone at m\/z 316. No oxycodone is observed in the light gray spectrum which is consistent with the black areas on the reconstructed image. Inset pictures show before and after LEMS analysis of oxycodone.<\/p>\n\n\n\n<div style=\"height:50px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-text-align-center\"><strong>LEMS Publications:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Brady, J.J., Judge, E.J., and Levis, R.J.,&nbsp;<em><a href=\"https:\/\/doi.org\/10.1002\/rcm.4226\">Mass spectrometry of intact neutral macromolecules using intense non-resonant femtosecond laser vaporization with electrospray post-ionization<\/a><\/em>, Rapid Commun. Mass Spectrom., (2009)&nbsp;<strong>23<\/strong>, 3151-3157.<\/li><li>Judge, E.J., Brady, J.J., Dalton, D.R. and Levis, R.J.,&nbsp;<em><a href=\"https:\/\/doi.org\/10.1021\/ac902880q\">Analysis of pharmaceutical compounds from glass, fabric, steel and wood surfaces at atmospheric pressure using non-resonant femtosecond laser vaporization, electrospray mass spectrometry<\/a><\/em>, Anal. Chem., (2010)&nbsp;<strong>82<\/strong>, 3231-3238.<\/li><li>Brady, J.J., Judge, E.J., and Levis, R.J.,&nbsp;<em><a href=\"https:\/\/doi.org\/10.1002\/rcm.4566\">Identification of Explosives and Explosive Formulations Using Laser Electrospray Mass Spectrometry<\/a><\/em>,&nbsp;Rapid Commun. Mass Spectrom., (2010)&nbsp;<strong>24<\/strong>, 1659-1664.<\/li><li>Judge, E.J., Brady, J.J., and Levis, R.J.,&nbsp;<em><a href=\"https:\/\/doi.org\/10.1021\/ac102409k\">Mass analysis of biological macromolecules at atmospheric pressure using nonresonant femtosecond laser vaporization and electrospray ionization<\/a><\/em>, Anal. Chem., (2010) <strong>82<\/strong>, 10203-10207.<\/li><li>Brady, J.J., Judge, E.J., and Levis, R.J.,&nbsp;<em><a href=\"https:\/\/doi.org\/10.1007\/s13361-010-0066-8\">Analysis of Amphiphilic Lipids and Hydrophobic Proteins Using Nonresonant Femtosecond Laser Vaporization with Electrospray Post-Ionization<\/a><\/em>, J. Am. Soc. Mass Spectrom., (2011)&nbsp;<strong>22<\/strong>, 762-772.<\/li><li>Judge, E.J., Brady, J.J., Barbano, P.E., and Levis, R.J.,&nbsp;<em><a href=\"https:\/\/doi.org\/10.1021\/ac102978f\">Nonresonant Femtosecond Laser Vaporization with Electrospray Postionization for ex vivo Plant Tissue Typing Using Compressive Linear Classification<\/a><\/em>, Anal. Chem., (2011)&nbsp;<strong>83<\/strong>, 2145-2151.<\/li><li>Brady, J.J., Judge, E.J., and Levis, R.J.,&nbsp;<em><a href=\"https:\/\/doi.org\/10.1073\/pnas.1105673108\">Nonresonant Femtosecond Laser Vaporization of Aqueous Protein Preserves Folded Structure<\/a><\/em>, P. Natl. Acad. Sci., (2011) <strong>108<\/strong>, 12217-12222.<\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>The objective of our research is to develop a new type of ambient mass spectrometric technique combining non-resonant fs laser vaporization and electrospray ionization. The two methods combined allows for the vaporization of neutral sample molecules using the nonresonant fs laser and post-ionization using the electrospray. Using laser electrospray mass spectrometry (LEMS) we have successfully&hellip;&nbsp;<a href=\"https:\/\/sites.temple.edu\/levislab\/laser-electrospray-mass-spectrometry\/\" rel=\"bookmark\">Read More &raquo;<span class=\"screen-reader-text\">Laser Electrospray Mass Spectrometry<\/span><\/a><\/p>\n","protected":false},"author":18090,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"","neve_meta_content_width":70,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":"","footnotes":""},"class_list":["post-135","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/sites.temple.edu\/levislab\/wp-json\/wp\/v2\/pages\/135","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.temple.edu\/levislab\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.temple.edu\/levislab\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.temple.edu\/levislab\/wp-json\/wp\/v2\/users\/18090"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.temple.edu\/levislab\/wp-json\/wp\/v2\/comments?post=135"}],"version-history":[{"count":0,"href":"https:\/\/sites.temple.edu\/levislab\/wp-json\/wp\/v2\/pages\/135\/revisions"}],"wp:attachment":[{"href":"https:\/\/sites.temple.edu\/levislab\/wp-json\/wp\/v2\/media?parent=135"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}