Amal M. Hamza1, Ali M. BenTaleb2, Sami J Alsabry1,
Nagib A. Elmarzugi3,4, Terin Adali1
1. National Medical Research Center, NASR, Alzawia, Libya
2. The Graduate School of Applied Sciences, Near East University, TRNC 10 Mersin, Turkey
3. Institute of Bioproduct Development, University Technology Malaysia
4. Faculty of Pharmacy, Tripoli University & Biotechnology Research Center, Libya
The current study focuses onto investigation of the effect of incubation time on PEG 400 and ctDNA biocomplex formation using Fourier-Transform Infra-Red (FTIR) spectroscopy. The influence of interaction time duration was studied using FTIR at three incubation time (zero, 1hr, and 48 hrs) at 1:1 PEG-DNA ratio. The experiment carried out at room temperature 22 C, with prior vortex stirrer of biocomplex for 10 min to improve homogeneity of sample. The results showed that the binding reaction of PEG and ctDNA proceeds rapidly through DNA base pairs and phosphate DNA backbone, and the complexation reached a maximum in 1hr after mixing PEG and ctDNA at 1:1 ratio.
The spectroscopic and structural analysis results was indicate that PEG binds with DNA, by weak to moderate complex formation with both hydrophilic and hydrophobic contacts through DNA base pair, with a little 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 and significant effect of incubation time in PEG-ctDNA biocomplex formation.
Finally, FTIR technique was shown rapid, good stability, and a valuable tool for studying the biological properties of PEG with ctDNA.
Key Words: Polyethylene Glycol 400, Calf thymus DNA, FTIR, Major Groove, Minor Groove.