Preparation of polypseudorotaxanes composed of cyclodextrin and polymers in microspheres

Chem Pharm Bull (Tokyo). 2014;62(10):962-6. doi: 10.1248/cpb.c14-00313.

Abstract

We prepared polypseudorotaxanes (PPRXs) composed of cyclodextrin (CyD) and polyethylene glycol (PEG) inside microspheres (MSs) by an emulsifying process using polypropylene glycol (PPG) that shows temperature-dependent hydrophilicity changes; PPG is hydrophobic at high temperatures but hydrophilic at low temperatures. An aqueous solution of CyD and PEG was dispersed as droplets in PPG at 60°C then cooled to 0°C to allow water of droplets to transfer into PPG. On removal of water in the droplets, CyD and PEG were left behind as a CyD/PEG PPRX inside the solid-state MSs. Examination of α-, β-, and γ-CyD revealed that α-CyD was suitable for the formation of PPRX containing PEG in this MS preparation procedure. Interestingly, a new PPRX composed of α-CyD and PPG was formed in the α-CyD MSs when they were prepared in the absence of PEG from the aqueous solution of α-CyD. This MS fabrication procedure can control the size and shape of PPRX particles, and will contribute to the production of new types of CyD inclusion complexes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclodextrins / chemistry*
  • Drug Carriers / chemistry
  • Hydrophobic and Hydrophilic Interactions
  • Microspheres*
  • Polymers / chemistry*
  • Propylene Glycols / chemistry*
  • Rotaxanes / chemical synthesis
  • Rotaxanes / chemistry*
  • Temperature

Substances

  • Cyclodextrins
  • Drug Carriers
  • Polymers
  • Propylene Glycols
  • Rotaxanes
  • polypropylene glycol