Publications

2021-2025

E. C. Tackman, D. N. Higgins, D. E. Kerecman, E-J. E. Ott, M. V. Johnston, and M. A. Freedman, "The Use of Transmission Electron Microscopy with Scanning Mobility Particle Size Spectrometry for an Enhanced Understanding of the Physical Characteristics of Aerosol Particles Generated with a Flow Tube Reactor." Aerosol Science and Technology (2023).

S. Jiang, M. J. Apsokardu, Y-R. Liu, C-Y. Wang, T. Huang, and M. V. Johnston, "Ion Formation Mechanism of Cortisone Molecules and Clusters in Charged Nanodroplets." Physical Chemistry Chemical Physics (2022).

D. N. Higgins, M. S. Taylor, J. M. Krasnomowitz, and M. V. Johnston, "Growth Rate Dependence of Secondary Organic Aerosol on Seed Particle Size, Composition, and Phase." ACS Earth and Space Chemistry (2022).

M. S. Taylor, D. N. Higgins, and M. V. Johnston, "Modelling Ultrafine Particle Growth Based on Flow Tube Reactor Measurements." Atmospheric Measurement Techniques (2022).

D. E. Kerecman, M. J. Apsokardu, S. L. Talledo, M. S. Taylor, D. N. Haugh, Y. Zhang, and M. V. Johnston, "Online Characterization of Organic Aerosol by Condensational Growth into Aqueous Droplets Coupled with Droplet-Assisted Ionization." Analytical Chemistry (2021).

Y. Zhang, M. J. Apsokardu, D. E. Kerecman, M. Achtenhagen, and M. V. Johnston, "Reaction Kinetics of Organic Aerosol Studied by Droplet Assisted Ionization: Enhanced Reactivity in Droplets Relative to Bulk Solution." Journal of the American Society for Mass Spectrometry (2021).

2016-2020

M. J. Apsokardu, J. M. Krasnomowitz, S. Jiang, and M. V. Johnston, "Ion Formation from Rapidly Heated Aqueous Droplets by Droplet Assisted Ionization." Journal of Physical Chemistry (2020).

L. Tiszenkel, C. M. Stangl, J. M. Krasnomowitz, Q. Ouyang, H. Yu, M. J. Apsokardu, M. V. Johnston, and S. Lee, "Temperature Effects on Sulfuric Acid Aerosol Nucleation and Growth: Initial Results from the TANGENT Study", Atmospheric Chemistry and Physics (2019), 19, 8915-8929.

M. V. Johnston and D. E. Kerecman, "Molecular Characterization of Atmospheric Organic Aerosol by Mass Spectrometry." Annual Review of Analytical Chemistry (2019), 12, 247-274.  [The link provided here gives complimentary one-time access to this article as a PDF file for your own personal use. Any further/multiple distribution, publication, or commercial usage of this copyrighted material requires submission of a permission request addressed to the Copyright Clearance Center (http://www.copyright.com/).]

C. M. Stangl, J. M. Krasnomowitz, M. J. Apsokardu, L. Tiszenkel, Q. Ouyang, S. Lee, and M. V. Johnston, "Sulfur Dioxide Modifies Aerosol Particle Formation and Growth by Ozonolysis of Monoterpenes and Isoprene." Journal of Geophysical Research Atmospheres (2019).

J. M. Krasnomowitz, M. J. Apsokardu, C. M. Stangl, L. Tiszenkel, Q. Ouyang, S. Lee, and M. V. Johnston, "Growth of Aitken mode ammonium sulfate particles by α-pinene ozonolysis", Aerosol Science and Technology (2019), 53, 406-418.

M. J. Apsokardu, D. E. Kerecman, and M. V. Johnston, "Ion formation in droplet-assisted ionization" Rapid Communications in Mass Spectrometry (2018) 0, 1-7.

M. J. Apsokardu, P. Tu, Y. Wu, and M. V. Johnston, “Impact of Multiphase Chemistry on Nanoparticle Growth and Composition”, in: Multiphase Environmental Chemistry in the Atmosphere, ACS Symposium Series vol. 1299 (2018), Chapter 2, pp. 9-34.

M. J. Apsokardu and M. V. Johnston, “Nanoparticle Growth by Particle Phase Chemistry”, Atmospheric Chemistry and Physics (2018) 18, 1-13.

S. Choi, M. Johnston, G.-S. Wang, and C. P. Huang, “A Seasonal Observation on the Distribution of Engineered Nanoparticles in Municipal Wastewater Treatment Systems Exemplified by TiO2 and ZnO”, Science of The Total Environment (2018) 625, 1321-1329.

B. R. Bzdek, J. W. DePalma, and M. V. Johnston, “Mechanisms of Atmospherically Relevant Cluster Growth”, Accounts of Chemical Research (2017) 50, 1965-1975.

A. J. Horan, J. M. Krasnomowitz, and M. V. Johnston, “Particle Size and Chemical Composition Effects on Elemental Analysis with the Nano Aerosol Mass Spectrometer”, Aerosol Science and Technology (2017) 51, 1135-1143.

C. Stangl and M. V. Johnston, “Aqueous Reaction of Dicarbonyls with Ammonia as a Potential Source of Organic Nitrogen in Airborne Nanoparticles”, Journal of Physical Chemistry A (2017) 121, 3720-3727.

S. Choi, M. V. Johnston, G.-S. Wang, and C. P. Huang, “Looking for Engineered Nanoparticles (ENPs) in Wastewater Treatment Systems: Qualification and Quantification Aspects”, Science of The Total Environment (2017) 590-591, 809-817.

Y. Wu and M. V. Johnston, “Aerosol Formation from OH Oxidation of the Volatile Cyclic Methyl Siloxane (cVMS) Decamethylcyclopentasiloxane”, Environmental Science and Technology (2017) 51, 4445-4451.

P. Tu and M. V. Johnston, “Particle Size Dependence of Biogenic Secondary Organic Aerosol Molecular Composition”, Atmospheric Chemistry and Physics (2017) 17, 7593-7603.

A. J. Horan, M. J. Apsokardu, and M. V. Johnston, “Droplet Assisted Inlet Ionization for Online Analysis of Airborne Nanoparticles”, Analytical Chemistry (2017) 89, 1059-1062.

J. M. Thomas, S. He, C. Larriba-Andaluz, J. W. DePalma, M. V. Johnston, and C. J. Hogan Jr., “Ion Mobility Spectrometry-Mass Spectrometry Examination of the Structures, Stabilities, and Extents of Hydration of Dimethylamine-Sulfuric Acid Clusters”, Physical Chemistry Chemical Physics (2016) 18, 22962-22972.

K. Hoang, M. Pophristic, A. J. Horan, M. V. Johnston, and C. N. McEwen, “High Sensitivity Analysis of Nanoliter Volumes of Volatile and Nonvolatile Compounds using Matrix Assisted Ionization (MAI) Mass Spectrometry”, Journal of The American Society for Mass Spectrometry (2016) 27, 1590-1596.

P. Tu, W. A. Hall IV, and M. V. Johnston, “Characterization of Highly Oxidized Molecules in Fresh and Aged Biogenic Secondary Organic Aerosol”, Analytical Chemistry (2016) 88, 4495-4501.

Y. Wu and M. V. Johnston, “Molecular Characterization of Secondary Aerosol from Oxidation of Cyclic Methylsiloxanes”, Journal of The American Society for Mass Spectrometry (2016) 27, 402-409.

2011-2015

J. W. DePalma, J. Wang, A. Wexler, and M. V. Johnston, “Growth of Ammonium Bisulfate Clusters by Adsorption of Oxygenated Organic Molecules”, Journal of Physical Chemistry A (2015) 119, 11191-11198.

J. W. DePalma, B. R. Bzdek, D. P. Ridge, and M. V. Johnston, “Activation Barriers in the Growth of Molecular Clusters Derived from Sulfuric Acid and Ammonia”, Journal of Physical Chemistry A (2014) 118, 11547-11554.

B. R. Bzdek, A. J. Horan, M. R. Pennington, N. J. Janechek, J. Baek, C. O. Stanier, and M. V. Johnson, “Silicon is a Frequent Component of Atmospheric Nanoparticles”, Environmental Science and Technology (2014) 48, 11137-11145.     (Click HERE for C&E News highlight)

B. R. Bzdek, M. J. Lawler, A. J. Horan, M. R. Pennington, J. W. DePalma, J. Zhao, J. N. Smith, and M. V. Johnston, “Molecular Constraints on Particle Growth during New Particle Formation”, Geophysical Research Letters (2014) 41, 6045-6054.

J. W. DePalma, D. J. Doren, and M. V. Johnston, “Formation and Growth of Molecular Clusters Containing Sulfuric Acid, Water, Ammonia and Dimethylamine”, Journal of Physical Chemistry A (2014) 118, 5464-5473.

M. R. Pennington, B. R. Bzdek, J. W. DePalma, J. N. Smith, A.-M. Kortelainen, L. Hildebrandt Ruiz, T. Petäjä, M. Kulmala, D. R. Worsnop, and M. V. Johnston,“Identification and Quantification of Particle Growth Channels during New Particle Formation”, Atmospheric Chemistry and Physics (2013) 13, 10215-10225.

B. R. Bzdek, A. J. Horan, M. R. Pennington, J. W. DePalma, J. Zhao, C. N. Jen, D. R. Hanson, J. N. Smith, P. H. McMurry, and M. V. Johnston, “Quantitative and Time-Resolved Nanoparticle Composition Measurements During New Particle Formation”, Faraday Discussions (2013) 165, 25-43.     (Click HERE for the general discussion of the manuscript)

J. W. DePalma, A. J. Horan, W. A. Hall IV, and M. V. Johnston, “Thermodynamics of Oligomer Formation: Implications for Secondary Organic Aerosol Formation and Reactivity”, Physical Chemistry Chemical Physics (2013) 15, 6935-6944.

M. V. Johnston, J. P. Klems, C. A. Zordan, M. R. Pennington, and J. N. Smith, “Selective Detection and Characterization of Nanoparticles from Motor Vehicles”, Research Report 173 (2013) Health Effects Institute, Boston, MA.

M. Kulmala, J. Kontkanen, H. Junninen, K. Lehtipalo, H. E. Manninen, T. Nieminen, T. Petäjä, M. Sipilä, S. Schobesberger, P. Rantala, A. Franchin, T. Jokinen, E. Järvinen, M. Äijälä, J. Kangasluoma, J. Hakala, P. P. Aalto, P. Paasonen, J. Mikkilä, J. Vanhanen, J. Aalto, H. Hakola, U. Makkonen, T. Ruuskanen, R. L. Mauldin III, J. Duplissy, H. Vehkamäki, J. Bäck, A. Kortelainen, I. Riipinen, T. Kurtén, M. V. Johnston, J. N. Smith, M. Ehn, T. F. Mentel, K. E. J. Lehtinen, A. Laaksonen, V.-M. Kerminen, and D. R. Worsnop,“Direct Observations of Atmospheric Nucleation”, Science (2013) 339, 943-946.

J. P. Klems and M. V. Johnston, “Origin and Impact of Particle-to-Particle Variations in Composition Measurements with the Nano Aerosol Mass Spectrometer”, Analytical and Bioanalytical Chemistry (2013) 405, 6995-7003.

W. A. Hall IV, M. R. Pennington, and M. V. Johnston, “Molecular Transformations Accompanying the Aging of Laboratory Secondary Organic Aerosol”, Environmental Science and Technology (2013) 47, 2230-2237.

B. R. Bzdek, J. W. DePalma, D. P. Ridge, J. Laskin, and M. V. Johnston, “Fragmentation Energetics of Clusters Relevant to Atmospheric New Particle Formation”, Journal of the American Chemical Society (2013) 135, 3276-3285.

A. J. Horan, Y. Gao, W. A. Hall IV, and M. V. Johnston, “Online Characterization of Particles and Gases with an Ambient Electrospray Ionization Source”, Analytical Chemistry (2012) 21, 9253-9258.

K. Adou, M. V. Johnston, and J. L. Dykins, “Targeted Absolute Quantification of Intact Proteins by Reversed Phase Liquid Chromatography-Mass Spectrometry (RPLC-MS), Charge Reduced Electrospray (CRES) and Condensation Particle Counting (CPC)”, Analytical Chemistry (2012) 84, 6981-6985.

B. R. Bzdek, M. R. Pennington, and M. V. Johnston, “Single Particle Chemical Analysis of Ambient Ultrafine Aerosol: A Review”, Journal of Aerosol Science (2012) 52, 109-120.

W. A. Hall IV and M. V. Johnston, “The Thermal Stability of Oligomers in Alpha-Pinene Secondary Organic Aerosol”, Aerosol Science and Technology (2012) 46, 983-989.

W. A. Hall IV and M. V. Johnston, “Oligomer Formation Pathways in Secondary Organic Aerosol from MS and MS/MS Measurements with High Mass Accuracy and Resolving Power”, Journal of the American Society for Mass Spectrometry (2012) 23, 1097-1108.

B. R. Bzdek, C. A. Zordan, M. R. Pennington, G. W. Luther III, and M. V. Johnston, “Quantitative Assessment of the Sulfuric Acid Contribution to New Particle Growth”, Environmental Science and Technology (2012) 46, 4365-4373.

J. P. Klems, C. A. Zordan, M. R. Pennington, and M. V. Johnston, “Chemical Composition of Ambient Nanoparticles on a Particle-by-Particle Basis”, Analytical Chemistry (2012) 84, 2253-2259.

M. R. Pennington, J. P. Klems, B. R. Bzdek, and M. V. Johnston, “Nanoparticle Chemical Composition and Diurnal Dependence at the CalNex Los Angeles Ground Site”, Journal of Geophysical Research – Atmospheres (2012) 117, D00V10. 

J. W. DePalma, B. R. Bzdek, D. J. Doren, and M. V. Johnston, “Structure and Energetics of Nanometer Size Clusters of Sulfuric Acid with Ammonia and Dimethylamine”, Journal of Physical Chemistry A (2012) 116, 1030-1040.              

M. R. Pennington and M. V. Johnston, “Trapping Charged Nanoparticles in the Nano Aerosol Mass Spectrometer (NAMS)”, International Journal of Mass Spectrometry (2012) 311, 64-71.

B. R. Bzdek, D. P. Ridge, and M. V. Johnston, “Amine Reactivity with Charged Sulfuric Acid Clusters”, Atmospheric Chemistry and Physics (2011) 11, 8735-8743.

J. P. Klems, M. R. Pennington, C. A. Zordan, L. McFadden, and M. V. Johnston,“Apportionment of Motor Vehicle Emissions from Fast Changes in Number Concentration and Chemical Composition of Ultrafine Particles Near a Roadway Intersection”, Environmental Science and Technology (2011) 45, 5637-5643.                               

A. S. Wexler and M. V. Johnston, “Real-Time Particle Analysis by Mass Spectrometry”, in: Aerosol Measurement: Principles, Techniques, and Applications, editors P. Kulkarni, P. A. Baron, and K. Willeke, John Wiley & Sons, New York, (2011) Chapter 11, pp. 233-254. 

B. R. Bzdek, C. A. Zordan, G. W. Luther III, and M. V. Johnston, “Nanoparticle Chemical Composition During New Particle Formation”, Aerosol Science and Technology (2011) 45, 1041-1048.

B. R. Bzdek, D. P. Ridge, and M. V. Johnston, “Reactivity of Methanesulfonic Acid Salt Clusters Relevant to Marine Air”, Journal of Geophysical Research – Atmospheres (2011) 116, D03301.

W. A. Hall IV and M. V. Johnston, “Oligomer Content of α–Pinene Secondary Organic Aerosol”, Aerosol Science and Technology (2011) 45, 37-45.

2006-2010

B. R. Bzdek, D. P. Ridge, and M. V. Johnston, “Size-Dependent Reactions of Ammonium Bisulfate Clusters with Dimethylamine”, Journal of Physical Chemistry A (2010) 114, 11638-11644.

J. P. Klems, M. R. Pennington, C. A. Zordan, and M. V. Johnston, “Ultrafine Particles Near a Roadway Intersection: Origin and Apportionment of Fast Changes in Concentration”, Environmental Science and Technology (2010) 44, 7903-7907.

Y. Gao, W. A. Hall IV, and M. V. Johnston, “Molecular Composition of Monoterpene Secondary Organic Aerosol at Low Mass Loading”, Environmental Science and Technology (2010) 44, 7897-7902.

C. A. Zordan, M. R. Pennington, and M. V. Johnston, “Elemental Composition of Nanoparticles with the Nano Aerosol Mass Spectrometer”, Analytical Chemistry (2010) 82, 8034-8038.

B. R. Bzdek and M. V. Johnston, “New Particle Formation and Growth in the Troposphere”, Analytical Chemistry (2010) 82, 7871-7878.                       

B. R. Bzdek, D. P. Ridge, and M. V. Johnston, “Amine Exchange into Ammonium Bisulfate and Ammonium Nitrate Nuclei”, Atmospheric Chemistry and Physics (2010) 10, 3495-3503.

Y. Gao and M. V. Johnston, “Online Deposition of Nano-Aerosol for Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry”, Rapid Communications in Mass Spectrometry (2009) 23, 3963-3968.

K. Adou and M. V. Johnston, “Flow Interface for Charge-Reduced Electrospray of Nanoparticle Solutions”, Analytical Chemistry (2009) 81, 10186-10192.

J. M. Spraggins, J. A. Lloyd, M. V. Johnston, J. Laskin, and D. P. Ridge, “Fragmentation Mechanisms of Oxidized Peptides Elucidated by SID, RRKM Modeling, and Molecular Dynamics”, Journal of the American Society for Mass Spectrometry (2009) 20, 1579-1592.

K. J. Heaton, R. L. Sleighter, P. G. Hatcher, W. A. Hall IV, and M. V. Johnston, “Composition Domains in Monoterpene Secondary Organic Aerosol”, Environmental Science and Technology (2009) 43, 7797-7802.

M. A. Dreyfus, K. Adou, S. M. Zucker, and M. V. Johnston, “Organic Aerosol Source Apportionment from Highly Time Resolved Molecular Composition Measurements”, Atmospheric Environment (2009) 43, 2901-2910.

J. A. Lloyd, K. J. Heaton, and M. V. Johnston, “Reactive Uptake of Trimethylamine into Ammonium Nitrate Particles”, Journal of Physical Chemistry A (2009) 113, 4840-4843.

J. A. Lloyd and M. V. Johnston, “An IT-TOF Mass Spectrometer for the Analysis of Organic Aerosol”, International Journal of Mass Spectrometry (2009) 281, 8-14.

K. J. Bein, Y. J. Zhao, M. V. Johnston, G. J. Evans, and A. S. Wexler, “Extratropical Waves Transport Boreal Wildfire Emissions and Drive Regional Air Quality Dynamics”, Journal of Geophysical Research – Atmospheres (2008) 113, D23213.

G. Ertem, A. M. Snellinger-O’Brien, M. C. Ertem, D. A. Rogoff, J. P. Dworkin, M. V. Johnston, and R. M. Hazen, “Abiotic Formation of RNA-Like Oligomers by Montmorillonite Catalysis: Part II”, International Journal of Astrobiology (2008) 7, 1-7.

C. A. Zordan, S. Wang, and M. V. Johnston, “Time-Resolved Chemical Composition of Individual Nanoparticles in Urban Air”, Environmental Science and Technology (2008) 42, 6631-6636.

K. J. Bein, Y. Zhao, M. V. Johnston, and A. S. Wexler, “Interactions Between Boreal Wildfire and Urban Emissions”, Journal of Geophysical Research – Atmospheres (2008) 113, D07304.

M. S. Reinard and M. V. Johnston, “Ion Formation Mechanism in Laser Desorption Ionization of Individual Nanoparticles”, Journal of the American Society for Mass Spectrometry (2008) 19, 389-399.

M. A. Dreyfus and M. V. Johnston, “Rapid Sampling of Individual Organic Aerosol Species in Ambient Air with the Photoionization Aerosol Mass Spectrometer”, Aerosol Science and Technology (2008) 42, 1-10.

A. S. Wexler and M. V. Johnston, “What Have We Learned from Highly Time Resolved Measurements During the EPA Supersite Program and Related Studies?”, Journal of the American Waste Management Association (2008) 58, 303-319.

F. Zhou and M. V. Johnston, “Hypersensitive Measurement of Proteins by Capillary Isoelectric Focusing and LC/MS”, in: Chromatographic Methods in Clinical Chemistry and Toxicology, editors R. Bertholf and R. Winecker, John Wiley and Sons, New York, (2007) Chapter 5, pp. 67-86. 

M. V. Johnston and M. A. Dreyfus, “Organic Particle Analysis off a Surface”, in: Encyclopedia of Mass Spectrometry, Volume 6: Ionization Methods, editors M. L. Gross and R. M. Caprioli, Elsevier, Amsterdam, (2007) Chapter 4, pp. 279-285.

D. M. Murphy, P. K. Hudson, D. J. Cziczo, S. Gallavardin, K. D. Froyd, M. V. Johnston, A. M. Middlebrook, M. S. Reinard, D. S. Thomson, T. Thornberry, and A. S. Wexler, “Distribution of Lead in Single Atmospheric Particles”, Atmospheric Chemistry and Physics (2007) 7, 3195–3210. 

K. J. Bein, Y. Zhao, M. V. Johnston, and A. S. Wexler, “Identification of Sources of Atmospheric PM at the Pittsburgh Supersite. Part III: Source Characterization”, Atmospheric Environment (2007) 41, 3974-3992. 

K. J. Heaton, M. A. Dreyfus, S. Wang, and M. V. Johnston, “Oligomers in the Early Stage of Biogenic SOA Formation and Growth”, Environmental Science and Technology (2007) 41, 6129-6136. 

G. A. Eiceman, D. Young, H. Schmidt, J. E. Rodriguez, J. I. Baumbach, W. Vautz, D. A. Lake, and M. V. Johnston, “Ion Mobility Spectrometry of Gas Phase Ions from Laser Ablation of Solids in Air at Ambient Pressure”, Applied Spectroscopy (2007) 61, 1076-1083. 

M. S. Reinard, K. Adou, J. M. Martini, and M. V. Johnston, “Source Characterization and Identification by Real-Time Single Particle Mass Spectrometry”, Atmospheric Environment (2007) 40, 9397-9409. 

F. Zhou and M. V. Johnston, “Intact Protein Profiling of Chlorobium tepidum by Capillary Isoelectric Focusing, Reversed Phase Liquid Chromatography and Mass Spectrometry”, Analytical Chemistry (2007) 79, 7145-7153.

M. P. Tolocka, K. J. Heaton, M. A. Dreyfus, S. Wang, C. A. Zordan, T. D. Saul, and M. V. Johnston, “Chemistry of Particle Inception and Growth During α-Pinene Ozonolysis”, Environmental Science and Technology (2006) 40, 1843-1848.

S. Wang, C. A. Zordan, and M. V. Johnston, “Chemical Characterization of Individual, Airborne Sub-10 nm Particles and Molecules”, Analytical Chemistry (2006) 78, 1750-1754.     (Click HERE for C&E News highlight) 

C. M. Wright, G. D. Christman, A. M. Snellinger, M. V. Johnston, and E. G. Mueller, “Direct Evidence for Enzyme Persulfide and Disulfide Intermediates during 4 Thiouridine Biosynthesis”, Chemical Communications (2006) 3104-3106.

M. P. Tolocka, M. S. Reinard, D. A. Lake, J. M. Ondov, A. S. Wexler, and M. V. Johnston, “Characterization of Short-term Particulate Matter Events by Real-Time Single Particle Mass Spectrometry”, Aerosol Science and Technology (2006) 40, 873 882. 

J. A. Lloyd, J. M. Spraggins, J. Laskin, and M. V. Johnston, “Peptide Ozonolysis: Product Structures and Relative Reactivities for Oxidation of Tyrosine and Histidine Residues”, Journal of the American Society for Mass Spectrometry (2006) 17, 1289-1298. 

T. D. Saul, M. P. Tolocka, and M. V. Johnston, “Reactive Uptake of Nitric Acid onto Sodium Chloride Aerosols Over a Wide Range of Relative Humidities”, Journal of Physical Chemistry A (2006) 110, 7614-7620.

J. M. Ondov, T. J. Buckley, P. K. Hopke, D. Ogulei, M. B. Parlangfe, W. F. Rogge, K. S. Squibb, M. V. Johnston, and A. S. Wexler, “Baltimore Supersite: Highly Time- and Size-resolved Concentrations of Urban PM2.5 and Its Constituents for Resolution of Sources and Immune Responses”, Atmospheric Environment (2006) 40, S224 S237.

N. J. Pekney, C. I. Davidson, K. J. Bein, A. S. Wexler, and M. V. Johnston, “Identification of Sources of Atmospheric PM at the Pittsburgh Supersite Part I: Single Particle Analysis and Filter-based Positive Matrix Factorization”, Atmospheric Environment (2006) 40, S411-S423.

K. J. Bein, Y. Zhao, N. J. Pekney, C. I. Davidson, M. V. Johnston, and A. S. Wexler, “Identification of Sources of Atmospheric PM at the Pittsburgh Supersite. Part II: Quantitative Comparisons of Single Particle, Particle Number, and Particle Mass Measurements”, Atmospheric Environment (2006) 40, S424-S444. 

C. S. Hamilton, T. M. Greco, C. A. Vizthum, J. M. Ginter, M. V. Johnston, and E. G. Mueller, “Mechanistic Investigations of the Pseudouridine Synthase RluA Using RNA Containing 5-Fluorouridine”, Biochemistry (2006) 45, 12029-12038.

M. V. Johnston, S. Wang, and M. S. Reinard, “Nanoparticle Mass Spectrometry: Pushing the Limit of Single Particle Analysis”, Applied Spectroscopy (2006) 60, 264A-272A. 

D. G. Nash, T. Baer, and M. V. Johnston, “Aerosol Mass Spectrometry: An Introductory Review”, International Journal of Mass Spectrometry (2006) 258, 2-12.

S. Wang and M. V. Johnston, “Airborne Nanoparticle Characterization with a Digital Ion Trap – Reflectron Time of Flight Mass Spectrometer”, International Journal of Mass Spectrometry (2006) 258, 50-57.

2000-2005

C. S. Hamilton, C. J. Spedaliere, J. M. Ginter, M. V. Johnston, and E. G. Mueller, “The Roles of the Essential Asp-48 and Highly Conserved His-43 Elucidated by the pH Dependence of the Pseudouridine Synthase TruB”, Archives of Biochemistry and Biophysics (2005) 433, 322-334.

M. P. Tolocka, D. A. Lake, M. V. Johnston, and A. S. Wexler, “Size-Resolved Fine and Ultrafine Particle Composition in Baltimore, Maryland”, Journal of Geophysical Research – Atmospheres (2005) 110, D07S04. 

K. J. Bein, Y. Zhao, A. S. Wexler, and M. V. Johnston, “Speciation of Size-Resolved Individual Ultrafine Particles in Pittsburgh, Pennsylvania”, Journal of Geophysical Research – Atmospheres (2005) 110, D07S05.

F. Zhou and M. V. Johnston, “Protein Profiling by Capillary Isoelectric Focusing, Reversed Phase Liquid Chromatography and Mass Spectrometry”, Electrophoresis (2005) 26, 1383-1388.

A. Clements, M. V. Johnston, B. S. Larsen, and C. N. McEwen, “Fluorescence-based Peptide Labeling and Fractionation Strategies for Analysis of Cysteine-containing Peptides”, Analytical Chemistry (2005) 77, 4495-4502.

M. A. Dreyfus, M. P. Tolocka, S. M. Dodds, J. Dykins, and M. V. Johnston, “Cholesterol Ozonolysis: Kinetics, Mechanism and Oligomer Products”, Journal of Physical Chemistry A (2005) 109, 6242-6248.

B. Zhao, Z. W. Yang, Z. G. Li, M. V. Johnston, and H. Wang, “Particle Size Distribution Function of Incipient Soot in Laminar Premixed Ethylene Flames: Effect of Flame Temperature”, Proceedings of the Combustion Institute, Part 1 (2005) 30, 1441 1448.

B. Oktem, M. P. Tolocka, B. Zhao, H. Wang, and M. V. Johnston, “Chemical Species Associated with the Early Stage of Soot Growth in a Laminar Premixed Ethylene Oxygen-Argon Flame”, Combustion and Flame (2005) 142, 364-373.

H. B. White III, S. D. Brown, and M. V. Johnston, “Contemporary Moral Problems in Chemistry: Impact of Peer Presentations on Awareness of Science and Society Issues”, Journal of Chemical Education (2005) 82, 1570-1576.

B. Oktem, M. P. Tolocka, and M. V. Johnston, “On-Line Analysis of Organic Components in Fine and Ultrafine Particles by Photoionization Aerosol Mass Spectrometry”, Analytical Chemistry (2004) 76, 253-261.     (Click HERE for C&E News highlight) 

M. P. Tolocka, T. D. Saul, and M. V. Johnston, “Reactive Uptake of Nitric Acid into Aqueous Sodium Chloride Droplets Using Real-Time Single-Particle Mass Spectrometry”, Journal of Physical Chemistry A (2004) 108, 2659-2665. 

M. P. Tolocka, M. Jang, J. M. Ginter, F. J. Cox, R. M. Kamens, and M. V. Johnston, “Formation of Oligomers in Secondary Organic Aerosol”, Environmental Science and Technology (2004) 38, 1428-1434.

M. P. Tolocka, D. A. Lake, M. V. Johnston, and A. S. Wexler, “Number Concentrations of Fine and Ultrafine Particles Containing Metals”, Atmospheric Environment (2004) 38, 3263-3273.

M. P. Tolocka, D. A. Lake, M. V. Johnston, and A. S. Wexler, “Ultrafine Nitrate Particle Events in Baltimore Observed by Real-Time Single Particle Mass Spectrometry”, Atmospheric Environment (2004) 38, 3215-3223.

F. Zhou and M. V. Johnston, “Protein Characterization by On-line Capillary Isoelectric Focusing, Reverse Phase Liquid Chromatography and Mass Spectrometry”, Analytical Chemistry (2004) 76, 2734-2740.

F. J. Cox, M. V. Johnston. K. Qian, and D. G. Peiffer, “Compositional Analysis of Isobutylene/p-Methylstyrene Copolymers by Matrix-Assisted Laser Desorption Ionization Mass Spectrometry”, Journal of the American Society for Mass  Spectrometry (2004) 15, 681-688.

D. A. Lake, M. P. Tolocka, M. V. Johnston, and A. S. Wexler, “The Character of Single Particle Sulfate in Baltimore”, Atmospheric Environment (2004) 38, 5311-5320.

J. M. Ginter, F. Zhou, and M. V. Johnston, “Generating Protein Sequence Tags by Combining Cone and Conventional Collision Induced Dissociation in a Quadrupole Time-of-Flight Mass Spectrometer”, Journal of the American Society for Mass Spectrometry (2004) 15, 1478-1486. 

C. J. Spedaliere, J. M. Ginter, M. V. Johnston, and E. G. Mueller, “The Pseudouridine Synthases: Revisiting a Mechanism that Seemed Settled”, Journal of the American Chemical Society (2004) 126, 12758-12759.

B. Zhao, Z. Yang, Z. Li, M. V. Johnston, and H. Wang, “Particle Size Distribution Function of Incipient Soot in Laminar Premixed Ethylene Flames: Effect of Flame Temperature”, Proceedings of the Combustion Institute (2004) 30, 1441-1448.

B. Zhao, Z. Wang, M. V. Johnston, H. Wang, A. Wexler, M. Balthaser, and M. Kraft, “Measurement and Numerical Simulation of Soot Particle Size Distribution Functions in a Laminar Premixed Ethylene-Oxygen-Argon Flame”, Combustion and Flame (2003) 133, 173-188.

F. J. Cox, A. Dasgupta, and M. V. Johnston, “Characterization and Relative Ionization Efficiencies of End-Functionalized Polystyrenes by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry”, Journal of the American Society for Mass Spectrometry (2003) 14, 648-657.

B. Zhao, Z. Wang, J.-J. Wang, M. V. Johnston, and H. Wang, “Analysis of Soot Nanoparticles in a Laminar Premixed Ethylene Flame by Scanning Mobility Particle Sizer”, Aerosol Science and Technology (2003) 37, 611-620. 

K. P. Rhoads, D. J. Phares, A. S. Wexler, and M. V. Johnston, “Size-Resolved Ultrafine Particle Composition Analysis, Part 1: Atlanta”, Journal of Geophysical Research – Atmospheres (2003) 108(D7), 8418.

D. J. Phares, K. P. Rhoads, M. V. Johnston, and A. S. Wexler, “Size-Resolved Ultrafine Particle Composition Analysis, Part 2: Houston”, Journal of Geophysical Research – Atmospheres (2003) 108(D7), 8420.

A. M. Middlebrook, D. M. Murphy, S.-H. Lee, D. S. Thomson, K. A. Prather, R. J. Wenzel, D.-Y. Liu, D. J. Phares, K. P. Rhoads, A. S. Wexler, M. V. Johnston, J. L. Jimenez, J. T. Jayne, D. R. Worsnop, I. Yourshaw, J. H. Seinfeld, R. C. Flagan, S. V. Hering, R. J. Weber, P. Jongejan, J. Slanina, and P. K. Dasgupta, “A Comparison of Particle Mass Spectrometers During the 1999 Atlanta SuperSite Experiment”, Journal of Geophysical Research – Atmospheres (2003) 108(D7), 8424.

T. Q. Shang, J. M. Ginter, M. V. Johnston, B. S. Larsen, and C. N. McEwen, “Carrier Ampholyte-Free Solution Isoelectric Focusing as a Prefractionation Method for the Proteomic Analysis of Complex Protein Mixtures”, Electrophoresis (2003) 24, 2359-2368.

D. A. Lake, M. P. Tolocka, M. V. Johnston, and A. S. Wexler, “Mass Spectrometry of Individual Particles Between 50 and 750 nm in Diameter at the Baltimore Supersite”, Environmental Science and Technology (2003) 37, 3268-3274.

F. J. Cox, K. Qian, A. O. Patil, and M. V. Johnston, “Microstructure and Composition of Ethylene-Carbon Monoxide Copolymers by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry”, Macromolecules (2003) 36, 8544 8550.

D. Young, K. M. Douglas, G. A. Eiceman, D. A. Lake, and M. V. Johnston, “Laser Desorption-Ionization of Polycyclic Aromatic Hydrocarbons from Glass Surfaces in an Ion Mobility Analysis”, Analytica Chimica Acta (2002) 453, 231-243.

D. B. Kane, J. J. Wang, K. Frost, and M. V. Johnston, “Detection of Negative Ions from Individual Ultrafine Particles”, Analytical Chemistry (2002) 74, 2092-2096. 

F. J. Cox, R. N. Feudale, M. V. Johnston, C. N. McEwen, and E. Hauptman, “Pyrolysis Photoionization Mass Spectrometry of Ethylene-Methyl Acrylate Copolymers”, Journal of Analytical and Applied Pyrolysis (2002) 64, 305-312.

D. B. Kane, B. Oktem, and M. V. Johnston, “Nanoparticle Detection by Aerosol Mass Spectrometry”, Aerosol Science and Technology (2001) 34, 520-527.

D. J. Phares, K. P. Rhoads, A. S. Wexler, D. B. Kane, and M. V. Johnston, “Application of the ART-2a Algorithm to Laser Ablation Aerosol Mass Spectrometry of Particle Standards”, Analytical Chemistry (2001) 73, 2338-2344.

M. V. Johnston, F. J. Cox, G. J. Forte, D. C. Nairn, R. S. Sacher, A. Z. Schwartz, and A. Vertes, “Remote Experimentation over the Net – Our First Year with MALDI”, Analytical Chemistry (2001) 73, 440A-445A.

D. B. Kane, B. Oktem, and M. V. Johnston, “An Electrostatic Lens for Focusing Charged Particles in a Mass Spectrometer”, Aerosol Science and Technology (2001) 35, 990-997.

A. S. Wexler and M. V. Johnston, “Real-Time Single-Particle Analysis”, Aerosol Measurement Principles, Techniques, and Applications, P. A. Baron and K. Willeke eds. (John Wiley & Sons, New York, 2001), Chapter 13, pp. 365-386. 

D. B. Kane and M. V. Johnston, “Enhancing the Detection of Sulfate Particles for Laser Ablation Aerosol Mass Spectrometry”, Analytical Chemistry (2001) 73, 5365-5369.

D. L. Zoller and M. V. Johnston, “Microstructures of Butadiene Copolymers Determined by Ozonolysis / MALDI Mass Spectrometry”, Macromolecules (2000) 33, 1664-1670.

J. L. Sterner, M. V. Johnston, G. R. Nicol, and D. P. Ridge, “Signal Suppression in Electrospray Ionization Fourier Transform Mass Spectrometry of Multi-component Samples”, Journal of Mass Spectrometry (2000) 35, 385-391.

W. P. Bartolini and M. V. Johnston, “Characterizing DNA Photo-Oxidation Reactions by High Resolution Mass Measurements with MALDI-TOF Mass Spectrometry”, Journal of Mass Spectrometry (2000) 35, 408-416.

M. V. Johnston, “Sampling and Analysis of Individual Particles by Aerosol Mass Spectrometry”, Journal of Mass Spectrometry (2000) 35, 585-595.

D. A. Lake, M. V. Johnston, C. N. McEwen, and B. S. Larsen, “Sample Preparation for High Throughput Accurate Mass Analysis by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry”, Rapid Communications in Mass Spectrometry (2000) 14, 1008-1013.

R. V. Mallina, A. S. Wexler, K. P. Rhoads, and M. V. Johnston, “High Speed Particle Beam Generation: A Dynamic Focusing Mechanism for Selecting Ultrafine Particles”, Aerosol Science and Technology (2000) 33, 87-104. 

D. L. Zoller, M. V. Johnston, K. Qian, and D. J. Lohse, “A Study of Deuterium Distribution in Deuterated Polyolefins by Pyrolysis-Photoionization Mass Spectrometry”, Macromolecules (2000) 33, 5388-5394.

H. B. White III, M. V. Johnston, and M. Panar, “Senior Seminar Focusing on Societal Issues Related to Chemistry and Biochemistry”, Journal of Chemical Education (2000) 77, 1590-1593.

D. B. Kane and M. V. Johnston, “Size and Composition Biases on the Detection of Individual Ultrafine Particles by Aerosol Mass Spectrometry”, Environmental Science and Technology (2000) 34, 4887-4893.