Formation and characterization of polylactide and β-cyclodextrin inclusion complex

Inclusion complex (ICs) of β-cyclodextrin (β-CD) and polylactide (PLA) were prepared by a solution-ultrasonic technique. Results showed that the feeding ratios of β-CD and PLA and the molecular weight of PLA had significant effects on the formation of the ICs, and the formed ICs could be dispersed in water when the molecular number weight (Mn) of PLA was lower than 100,000, whereas they agglomerated when the Mn of PLA reached 500,000 or more. The structures of the ICs were verified by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and wide-angle X-ray diffraction (WAXD). Results for surface contact angle prove that, compared to PLA, the hydrophilicity of the inclusion complex was obviously improved. The results of thermogravimetric analysis (TGA) indicated that the ICs had a lower glass transition temperature than pure PLA had. The ICs of PLA and β-CD show great potential as tissue engineering scaffold.