Spectroscopic Characterization of PEG-DNA Biocomplexes by FTIR

Abstract

Understanding the mode involved in the binding of certain molecules to DNA is of prime importance, and PEG offers wide-ranging applications in biological, medical and pharmaceutical contexts. FTIR spectroscopy has been used to characterize how the formed biocomplexes bind or dissociate to/from each other between PEG400-ctDNA under different conditions. Characterization and investigation of the effect of incubation time on PEG400-ctDNA biocomplexes formation were studied through spectroscopic technique FTIR. The influence of time duration and incubation on intermolecular interaction was analysed at three different selected times (Zero, 1hr, and 48 hrs.) at 1:1 PEG400-ctDNA monomer to nucleotide ratio. The experiment was carried out at room temperature 22 ºC, with prior vortex stirrer of biocomplex for 10 min to improve homogeneity of sample. The results showed that the binding reaction of PEG400-ctDNA proceeds rapidly through DNA base pairs and phosphate DNA backbone, and complexation was reached after a maximum 1hr after mixing PEG400 and ctDNA at 1:1 ratio. FTIR spectroscopy results suggest that PEG400 binds with ctDNA by weak to moderate biocomplexes formation, with both hydrophilic and hydrophobic contact through DNA base pairs, with minor binding preference towards phosphate backbone of DNA helix. The mode of interaction most likely referred to an interaction through outside groove binding or electrostatic binding modes. FTIR highlighted the significant effect of incubation time on the stable biocomplexes of non-ionic PEG400 and ctDNA. Moreover, FTIR spectroscopy technique was rapid, showed good stability, and is a valuable tool for studying the biological properties of biocomplexes of PEG400 and ctDNA.

Ionic Liquid-Mediated Preparation of Noncytotoxic Hemocompatible Stable DNA−ε-Poly-l-lysine Polyplexes: A New Sustainable Approach for the Bulk Production of Potential Nonviral Vectors for Gene Delivery Applications

“…As can be seen in the spectra, the characteristic bands of phosphate groups of DNA are absent in water, while they appeared in ILs with lower intensity, and hence, it can be concluded that in ILs the interactions between DNA phosphate and PLL retains the structural integrity of DNA. This result found here is similar to the DNA–PEG complex prepared for the gene delivery, where it was proposed that the weak interaction with phosphate groups decreases the chances of nonspecific interactions, which is desirable in gene delivery . Because the condensation of DNA is normally provoked by multivalent cations such as polyamines, positively charged polymers, and peptides .…”

“…This result found here is similar to the DNA−PEG complex prepared for the gene delivery, where it was proposed that the weak interaction with phosphate groups decreases the chances of nonspecific interactions, which is desirable in gene delivery. 42 Because the condensation of DNA is normally provoked by multivalent cations such as polyamines, positively charged polymers, and peptides. 43 Herein, the condensation of DNA might have happened due to the presence of PLL in IL.…”

Fabrication and Investigation of (PVA/PAA/Ag) nanocomposites for Antibacterial Application

“…It is obtained that the n rises with the rising of the content of Ag NPs. This action due to the rise of the density of nanocomposites [23].…”