TY - JOUR T1 - Strong ionic interactions in noncovalent complexes between poly(ethylene imine), a cationic electrolyte, and Cibacron Blue, a nucleotide mimic--implications for oligonucleotide vectors. AU - Çelikbıçak,Ömür, AU - Salih,Bekir, AU - Wesdemiotis,Chrys, PY - 2014/02/07/received PY - 2014/04/15/revised PY - 2014/04/15/accepted PY - 2014/7/22/entrez PY - 2014/7/22/pubmed PY - 2015/5/12/medline KW - ion pairs KW - noncovalent complexes KW - nucleotide mimic KW - poly(ethylene imine) KW - polymer-biomolecule interactions SP - 597 EP - 607 JF - Journal of mass spectrometry : JMS JO - J Mass Spectrom VL - 49 IS - 7 N2 - Cationic polymers can bind DNA to form polyplexes, which are noncovalent complexes used for gene delivery into the targeted cells. For more insight on such biologically relevant systems, the noncovalent complexes between the cationic polymer poly(ethylene imine) (PEI) and the nucleotide mimicking dye Cibacron Blue F3G-A (CB) were investigated using mass spectrometry methods. Two PEIs of low molecular weight were utilized (Mn ≈ 423 and 600 Da). The different types of CB anions produced by Na(+)/H(+) exchanges on the three sulfonic acid groups of CB and their dehydrated counterparts were responsible for complex formation with PEI. The CB anions underwent noncovalent complex formation with protonated, but not with sodiated PEI. A higher proportion of cyclic oligomers were detected in PEI423 than PEI600, but both architectures formed association products with CB. Tandem mass spectrometry studies revealed a significantly stronger noncovalent interaction between PEI and dehydrated CB than between PEI and intact CB. SN - 1096-9888 UR - https://www.unboundmedicine.com/medline/citation/25044844/Strong_ionic_interactions_in_noncovalent_complexes_between_poly_ethylene_imine__a_cationic_electrolyte_and_Cibacron_Blue_a_nucleotide_mimic__implications_for_oligonucleotide_vectors_ DB - PRIME DP - Unbound Medicine ER -