High Stability Aggregation Obtained Using Hydrophilic-Hydrophobic Block Copolymer Based on Poly(trimethylene carbonate)

Abstract

Biodegradable polymers can be used in living systems. One such biodegradable polymer that has attracted considerable attention in recent years is poly(trimethylene carbonate) (PTMC). In this study, poly(ethylene glycol) monomethyl ether (mPEG), which has hydrophilic properties, was used as the initiator for PTMC synthesis. The mPEG-PTMC block copolymer exhibits amphiphilicity and forms a very stable aggregation in a solvent. In our previous study, mPEG-PTMC aggregations that remained stable for two months in a methanol solvent were prepared. In the present study, the aggregation of this polymer could be maintained in a stable state for 1 year in ultrapure water owing to the hydrophilic segment of mPEG. Additionally, examination of the encapsulation properties of the aggregation was also performed using 8-anilino-1-naphthalenesulfonic acid. Encapsulation of the aggregation caused the intensity of the fluorescence to become high and the maximum fluorescence wavelength to shift to the short wavelength resion with increasing polymer concentration. The high stability and encapsulation property of this aggregation will facilitate application of this polymer to drug delivery systems.