| Presented in this dissertation are the results of the experiments dedicated to the investigation of the gas phase stability and reactivity of noncovalently bound species including coordination compounds of the first-row transition metal cations and adducts of selected oligodeoxynucleotides with metal ions and complexes. Electrospray Ionization Tandem Mass Spectrometry and Electrospray Ionization SIFT Mass Spectrometry combined with theoretical calculations were employed here to gain insights into the gas phase structures and energetics of the selected noncovalent assemblies.;For the first time a combination of ESI Tandem and ESI SIFT Mass Spectrometry with theoretical computations was utilized to explore and understand intrinsic reactivity of a trideoxynucleotide CCC with a proton donor gaseous HBr as well as relative stability of the multiply deprotonated oligonucleotide against collision induced dissociation. Computations of the proton affinities and minimum energy gas-phase structures of the CCC anions were performed by Dr. Einar Uggerud.;Versatile ESI tandem mass spectrometric approach was illustrated to help understand the fundamental principles of the recognition of a hexameric duplex d(5'GCATGC) by metallocomplexes. Experimental results generated with the trianionic duplex provided evidence for specific binding modes of the model DNA with selected metalloantibiotics (Bleomycin A2) and metallocomplexes (Ligands = 1,10-phenanthroline and triethylenetetramine.;A rare opportunity has been grasped to compare solution and gas phase stabilities of singly- doubly- and triply-ligated complexes of 1,10-phenanthroline with the first row transition metal dications. DFT calculations provided the intrinsic energetics of ligand loss from the metallocomplexes with and without concomitant electron transfer that allowed gaining further insight into the processes observed in the gas phase (these calculations were performed by Dr. Xiang Zhao). |
