α-Tocopherol loaded thermosensitive polymer nanoparticles: preparation, in vitro release and antioxidant properties

Abstract

Sbstractα-Tocopherol is the most bioavailable and active compound found in vitamin E with potential application in pharmaceutical, alimentary and cosmetic industries. However, its low solubility in aqueous medium and environmental instability limit its dosage. In this paper, we report the preparation of α-tocopherol loaded nanoparticles (TOC-NP) based on amphiphilic thermosensitive triblock copolymers PNIPAM-b-PCL-b-PNIPAM. The nanoparticles exhibited a core -shell structure, were positively charged and presented average diameters below 300 nm. TOC-NP presented controlled release of α-tocopherol at room temperature along 140h, and exhibited antioxidant properties in aqueous medium.

Alpha-tocopherol-loaded polycaprolactone nanoparticles improve the inflammation and systemic oxidative stress of arthritic rats

“…Although α-tocopherol-loaded poly-ε-caprolactone nanoparticles have been already characterized and its antioxidant effect demonstrated in vitro , 20 , 21 , 22 the present study shows that this formulation is also effective in vivo. The higher effectiveness of α-tocopherol-loaded polycaprolactone nanoparticles is probably related not only to the improvement of the solubility of α-tocopherol in the aqueous medium, but also because encapsulation introduces factors that can improve the releasing profile of α-tocopherol in the gastrointestinal tract.…”

“…For this reason, many strategies have been used to improve the aqueous solubility of α-tocopherol, including its introduction into nanoparticles prepared with biodegradable polyesters, such as poly-ε-caprolactone, what further allows the controlled release of the compound in the gastrointestinal tract. 20 , 21 , 22 This should improve the bioavailability of orally administered α-tocopherol and therefore decrease its effective dose.…”

Enhancing the performance of PEG-b-PCL-based nanocarriers for curcumin through its conjugation with lipophilic biomolecules

“…CUR-loaded nanoparticles were prepared through a modified nanoprecipitation method. 32 In a typical procedure, 80 mg of a copolymer and 20 mg of CUT were completely dissolved in 10 mL of THF. This solution was slowly dropped to 20.0 mL of deionised water under continuous magnetic stirring.…”