Raman and Rayleigh scattering study of crystalline polyoxyethyleneglycols

Abstract

Results of the study of Raman and Rayleigh scattering in crystalline polyoxyethyleneglycols (PEG) and PEG 1500 aqueous solution are reported. The conformational changes of the polymer chain have been studied as a function of PEG water solution concentration and molecular weight. Intensity ratios of the gauche and trans conformation around C-C and C-O bonds have been estimated from the Raman spectra. Moreover, from the Raman band parameters the values of the order parameters versus aqueous solution concentration have been determined. The influence of an external electric field on these parameters has been analysed. Mutual orientation of polyoxyethyleneglycol chains in the crystalline and liquid state has been studied on the basis of the angular correlation parameters obtained from the Rayleigh band intensity as a function of aqueous solution concentration and molecular weight.

Self-Assembly of PEGylated Peptide Conjugates Containing a Modified Amyloid β-Peptide Fragment

“…Raman bands at 1661 cm −1 and 1603 cm −1 in Figure are associated with antiparallel β-sheet structure, in good agreement with FTIR results for the same sample in solution (Figure c). The region of the Raman spectra in Figure with wave numbers 1000−1500 cm −1 is very similar to the data reported in the literature for crystallized PEG600 . In particular, (A) is the region of the C−O vibration and (B) is the region of the C−C vibration in the PEG chain …”

“…The region of the Raman spectra in Figure with wave numbers 1000−1500 cm −1 is very similar to the data reported in the literature for crystallized PEG600 . In particular, (A) is the region of the C−O vibration and (B) is the region of the C−C vibration in the PEG chain …”

“…The region of the Raman spectra in Figure 7 with wave numbers 1000-1500 cm -1 is very similar to the data reported in the literature for crystallized PEG600. 50 In particular, (A) is the region of the C-O vibration and (B) is the region of the C-C vibration in the PEG chain. 50 X-ray diffraction from a dried stalk was also used to investigate the morphology in the solid state and the influence of the PEG crystallization on the β-sheet structure of the samples.…”

“…50 In particular, (A) is the region of the C-O vibration and (B) is the region of the C-C vibration in the PEG chain. 50 X-ray diffraction from a dried stalk was also used to investigate the morphology in the solid state and the influence of the PEG crystallization on the β-sheet structure of the samples. Figure 8 contains some representative XRD patterns.…”

PEG400 novel phase description in water

“…This spectrophotometric argument, as well as the amphiphilic arguments used below, make it not very likely for PEG to adopt the structure with oxygen bridges outside, as it has been possible to argue in other situations, namely in simulations at 0 K, very far from our experimental conditions [15]. Recent spectroscopic data [16], particularly Raman scattering, confirm the conformational change in crystalline polyoxyethylene glycol and PEG Fig. 7.…”