Synthesis and characterization of a thermosensitive hydrogel based on biodegradable amphiphilic PCL-Pluronic (L35)-PCL block copolymers

Thermosensitive PEG–PCL–PEG Hydrogel Controlled Drug Delivery System: Sol–Gel–Sol Transition and In Vitro Drug Release Study

“…The hysteresis might be attributed to the two primary reasons. First, the crystallization rate of melting PCL block in water was very slow and the partial microcrystalline structure could be formed only after longer time;34 In addition, the hydrophobic interaction of the melt and swollen PCL block hydrophobic clusters weakened on cooling, which should also cause the hysteresis in the phase transition temperature than that on heating procedure 35, 36…”

Biodegradable poly(ɛ-caprolactone)–poly(ethylene glycol) copolymers as drug delivery system

“…However, An et al (2001) reported that the PCL-PEG-PCL system did not show lower gel-sol transition at any composition and the sol-gel transition on cooling. Just recently, Bae et al (2005) found that PCL-PEG-PCL triblock copolymer aqueous solution (>15 wt%) underwent the sol-gel-sol transition as the temperature increased from 10 • C to 60 • C. Liu et al (2007a) found that the gel-sol phase transition behavior of PCL-PEG-PCL copolymers was dependent on hydrophilic/hydrophobic balance in macromolecular structure, as well as on heating history of copolymer aqueous solution. In their further contribution, by adjusting the PCL/PEG balance and molecular weight of PCL-PEG-PCL copolymer, Gong et al reported the sol-gel-sol transition of PCL-PEG-PCL hydrogels as the temperature increased (shown in Fig.…”

Solubilization of TX-100™ and PEG-PPG-PEG in Liquid Carbon Dioxide

“…TX-100 TM (MW $ 625 g=mol) is slightly hydrophilic, nonionic, and biodegradable. It is used as a wetting agent and emulsifier (15). The PEG-PPG-PEG (MW$1100 g=mol) is very hydrophilic, nonionic, non-biodegradable and used as solubilizers, emulsifiers, and wetting agents (13).…”