Physical Sciences and Mathematics Commons^™

Mechanism Of Protein Charging And Supercharging In Electrospray Ionization: Molecular Dynamics Simulations And Experimental Investigations, Haidy S. Metwally

Electronic Thesis and Dissertation Repository

Electrospray ionization mass spectrometry (ESI-MS) is a powerful technique for investigating protein structures, conformations, and interactions. Despite its widespread use, many fundamental aspects of ESI remain poorly understood. In this thesis, we use a combination of molecular dynamics (MD) simulations and experiments to gain insights into the hidden complexities of ESI-MS.

Chapter 2 discusses the topic of salt-induced protein signal degradation. Salts such as NaCl, CsCl, and tetrabutyl ammonium chloride (NBu₄Cl) interfere with MS data acquisition, leading to adduct formation and signal suppression. MD simulations provide an explanation for these salt interferences. Signal suppression can be broken down …

Cross Photoreaction Of Glyoxylic And Pyruvic Acids In Model Aqueous Aerosol, Sha-Sha Xia, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

Aerosols of variable composition, size, and shape are associated with public health concerns as well as with light-particle interactions that play a role in the energy balance of the atmosphere. Photochemical reactions of 2-oxocarboxylic acids in the aqueous phase are now known to contribute to the total secondary organic aerosol (SOA) budget. This work explores the cross reaction of glyoxylic acid (GA) and pyruvic acid (PA) in water, the two most abundant 2-oxocarboxylic acids in the atmosphere, under solar irradiation and dark thermal aging steps. During irradiation, PA and GA are excited and initiate proton-coupled electron transfer or hydrogen abstraction …