Electrospray-ionization mass spectrometry for screening the specificity and stability of single-stranded-DNA templated self-assemblies.
Supramolecular complexes consisting of a single-stranded oligothymine (dTn) as the host template and an array of guest molecules equipped with a complementary diaminotriazine hydrogen-bonding unit have been studied with electrospray-ionization mass spectrometry (ESI-MS). In this hybrid construct, a supramolecular stack of guest molecules is hydrogen bonded to dTn. By changing the hydrogen-bonding motif of the DNA host template or the guest molecules, selective hydrogen bonding was proven. We were able to detect single-stranded-DNA (ssDNA)-guest complexes for strands with lengths of up to 20 bases, in which the highest complex mass detected was 15 kDa; these complexes constitute 20-component self-assembled objects. Gas-phase breakdown experiments on single- and multiple-guest-DNA assemblies gave qualitative information on the fragmentation pathways and the relative complex stabilities. We found that the guest molecules are removed from the template one by one in a highly controlled way. The stabilities of the complexes depend mainly on the molecular weight of the guest molecules, a fact suggesting that the complexes collapse in the gas phase. By mixing two different guests with the ssDNA template, a multicomponent dynamic library can be created. Our results demonstrate that ESI-MS is a powerful tool to analyze supramolecular ssDNA complexes in great detail.
Janssen
Pim G A
PG
Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands.
van Dongen
Joost L J
JL
Meijer
E W
EW
Schenning
Albertus P H J
AP
D020650:Combinatorial Chemistry Techniques; D004277:DNA, Single-Stranded / Q000032:analysis* / Q000737:chemistry*; D005740:Gases / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013379:Substrate Specificity; D013698:Templates, Genetic; D013941:Thymine / Q000737:chemistry
D004277:DNA, Single-Stranded; D005740:Gases; D009930:Organic Chemicals; D013941:Thymine