Amal Abdulrahman
Clark Atlanta University, USA
Title: A new perspective for possible formulation and characterization of beta- cyclodextrin/ poly(ethylene glycol) crystalline inclusion complexes
Biography
Biography: Amal Abdulrahman
Abstract
In literature, there is a disagreement regarding whether or not β-CD forms inclusion complexes with Polyethylene Glycol (PEG). In a publication in 1993 Harada et al. reported the complexation between CDs with several polymers including PEG. They reported PEG forms inclusion complexes with α-CD and γ-CD; however, it does not form such complexes with the β-CD. Researchers still agree and cite this article to continue the classification of PEG as being impenetrable within the β-CD cavity. However, there is one communication in 2000 reported the formation of the crystalline complex between PEG and β-CD demonstrating this via a single crystal preparation. However, this work did not report the used molecular weights of PEG/PEO. Furthermore, most PEGs/PEOs have a distribution of molecular weight suggesting that preparing a single crystal for a mixture of molecular weights would be difficult. One plausible explanation for β-CD/PEG single crystal formation is the complexation method. As a next step to our report on the inclusion complexes of β-CD with β-sitosterol, we prepared β-CD crystalline inclusion complexes with different molecular weights of PEG. The suggestion of the formation of β-CD/PEG inclusion complexes was supported by NMR, FTIR, X-Ray diffraction, and SEM. The study clearly demonstrated the formation of crystalline inclusion complexes in the solid state, and via 2-D NMR spectroscopy, in the solution state, that the methylene protons of the PEG repeat units interact with both the internal and external protons of the β-CDs. The examination of drugs solubility in water is as an example of our future work.