Poly(ethyl glycol) assisting water sorption enhancement of poly(ε‐caprolactone) blend for drug delivery

Abstract

Poly(e-caprolactone) (PCL) has been thermally synthesized, and then fractionated to blend with poly(ethyl glycol) (PEG). Blend films of PCL and PEG have been prepared by solution casting. Fourier transform infrared spectrum and differential scanning calorimetry of the films have been carried out, and the results indicate some hydrogen bonding interaction between the two components, which is resulted from the carbonyl groups of PCL and the hydroxyl end-groups of the low-molecularweight PEG. Scanning electron microscope images of the blend films reveal porous network structures for their surfaces and for their inner parts and the porous structure becomes more pronounced with the increase of PEG in the blend film. Ibuprofen (IBU) was used as the model drug to test the drug release behavior for the PCL/PEG blend matrices. The results show that IBU could be released from the blend tablets rapidly, and the release rate increases with PEG content. Analysis of the release profiles indicates PCL erosion control release mechanism of pure PCL tablet, but drug diffusion control of the blend tablet, because PEG can absorb water to allow water feasible to diffuse into drug core and dissolve drug. Therefore, the interconnected channels in the blend matrices and the hydrophilic nature of PEG contribute to the improvement of the IBU release rate. The research indicates that drug release rate from PCL based material could be efficiently improved by addition of small amount of hydrophilic lowmolecular-weight PEG.

Long-Term Evaluation of Dip-Coated PCL-Blend-PEG Coatings in Simulated Conditions

“…Our study offers a better understanding of the long-term degradation of PCL-blend-PEG coatings. PEG and PCL are immiscible polymers and they phase-separate in the solid state, as recently reported in the literature [67][68][69]. Therefore, in an early stage, after the PCL-blend-PEG's immersion, the first released material is mainly identified as the water-soluble PEG component, while for long term immersion periods, residual products of insoluble CL oligomers result due to the slow degradation of the PCL [70].…”

Controlled NO-Release from 3D-Printed Small-Diameter Vascular Grafts Prevents Platelet Activation and Bacterial Infectivity

“…A widely used approach to control the NO-releasing rate is incorporation of polymers such as poly­(ethylene glycol) (PEG) and polycaprolactone (PCL) with RSNOs as donor-storing agents. , PEG is a well-known hydrophilic polymer, forming water-swollen networks, , and polycaprolactone (PCL) is a hydrophobic, semicrystalline, and biocompatible linear aliphatic polyester, which is slowly degradable, and both are FDA approved. , Blending of PEG and PCL in the solvent can reduce the interfacial tension of the solution. Therefore, the shrinkage of coating after solvent evaporation would be greater in a PEG–PCL layer compared to a pure PCL layer, and consequently the porosity of the PEG–PCL layer would be higher . The formed porous microstructure is advantageous for diffusion and entrapment of PBS to enhance water uptake and facilitate the NO release.…”

Tricalcium Phosphate Sol-Incorporated Poly(ε-caprolactone) Membrane with Improved Mechanical and Osteoinductive Activity as an Artificial Periosteum

“…For the membranes before immersion, all the curves showed two characteristic peaks at 21.8°(110) and 23.5°(200), confirming the semi-crystalline structures of PCL. 44 The loading of the TCP sol had no other new diffraction peaks, indicating that the TCP sol was an amorphous structure containing −(Ca−O− P) n − oligomers. 45,46 With the introduction of TCP sol, the peaks of P20T1 and P10T1 become weaker compared to P1T0, inferring that TCP sol weakened the interaction of PCL molecular chains and decreased the crystallinity of PCL, which is consistent with the results of DSC.…”