title: Encapsulation of CO2 into amorphous and crystalline α-cyclodextrin powders and the characterization of the complexes formed.
abstract: Carbon dioxide complexation was undertaken into solid matrices of amorphous and crystalline α-cyclodextrin (α-CD) powders, under various pressures (0.4-1.6 MPa) and time periods (4-96 h). The results show that the encapsulation capacity of crystalline α-CD was significantly lower than that of amorphous α-CD at low pressure and short time (0.4-0.8 MPa and 4-24 h), but was markedly enhanced with an increase of pressure and prolongation of encapsulation time. For each pressure level tested, the time required to reach a near equilibrium encapsulation capacity of the crystalline powder was around 48 h, which was much longer than that of the amorphous one, which only required about 8h. The inclusion complex formation of both types of α-CD powders was confirmed by the appearance of a CO2 peak on the FTIR and NMR spectra. Moreover, inclusion complexes were also characterized by DSC, TGA, SEM and X-ray analyses.
authors.affiliation: School of Agriculture and Food Sciences, The University of Queensland, QLD 4072, Australia.
authors.forename: Thao M
authors.initials: TM
authors.lastname: Ho
authors.affiliation: School of Chemical Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia.
authors.forename: Tony
authors.initials: T
authors.lastname: Howes
authors.affiliation: School of Agriculture and Food Sciences, The University of Queensland, QLD 4072, Australia. Electronic address: b.bhandari@uq.edu.au.
authors.forename: Bhesh R
authors.initials: BR
authors.lastname: Bhandari
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D003460:Crystallization; D005524:Food Technology / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D011208:Powders; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014961:X-Ray Diffraction; D047391:alpha-Cyclodextrins / Q000737:chemistry*
chemical_list: D011208:Powders; D047391:alpha-Cyclodextrins; D002245:Carbon Dioxide; C032613:alpha-cyclodextrin
keywords: Carbon dioxide; Inclusion complex; Solid encapsulation; α-Cyclodextrin powder