Nanoparticles with entrapped α-tocopherol: synthesis, characterization, and controlled release

Abstract

An emulsion evaporation method was used to synthesize spherical poly(DL-lactide-co-glycolide) (PLGA) nanoparticles with entrapped α-tocopherol. Two different surfactants were used: sodium dodecyl sulfate (SDS) and poly(vinyl alcohol) (PVA). For SDS nanoparticles, the size of the nanoparticles decreased significantly with the entrapment of α-tocopherol in the PLGA matrix, while the size of PVA nanoparticles remained unchanged. The polydispersity index after synthesis was under 0.100 for PVA nanoparticles and around 0.150 for SDS nanoparticles. The zeta potential was negative for all PVA nanoparticles. The entrapment efficiency of α-tocopherol in the polymeric matrix was approximately 89% and 95% for nanoparticles with 8% and 16% α-tocopherol theoretical loading, respectively. The residual PVA associated with the nanoparticles after purification was approximately 6% ( w/w relative to the nanoparticles). The release profile showed an initial burst followed by a slower release of the α-tocopherol entrapped inside the PLGA matrix. The release for nanoparticles with 8% α-tocopherol theoretical loading (86% released in the first hour) was faster than the release for the nanoparticles with 16% α-tocopherol theoretical loading (34% released in the first hour).

Processing of phosphocasein dispersions by dynamic high pressure: Effects on the dispersion physico-chemical characteristics and the binding of α-tocopherol acetate to casein micelles

“…Different strategies have already been tested to carry vitamin E with the aim of enhancing its stability and bioavailability: (i) entrapment of α-tocopherol into polymeric nanoparticles of poly(DL-lactide-co-glycolide) (PLGA) using sodium dodecyl sulphate (SDS) or poly(vinyl alcohol) (PVA) as surfactant and the emulsion evaporation method (Zigoneanu, Astete, & Sabliov, 2008); (ii) loading of vitamin E into the oily phase of Nano-O/W-emulsions stabilised by sodium caseinate or low M.W. surfactants (Relkin, Yung, Kalnin, & Ollivo, 2008;Hatanaka et al, 2010); (iii) entrapment of α-tocopherol into globular protein aggregates or hydrogels using the cold-set aggregation/gelation technique (Somchue, Sermsri, Shiowatana, & Siripinyanond, 2009); (iv) formation of a β-Lactoglobulin/α-tocopherol complex to study tocopherol air-and light-stability (Liang, Tremblay-Hébert, & Subirade, 2011).…”

In vitro release of α-tocopherol from emulsion-loaded β-lactoglobulin gels

“…The lipophilic compound a-tocopherol is the most abundant and biologically active form of vitamin E. Its principal role as an antioxidant is based on the formation of a highly stable a-tocopheroxyl radical by loss of a phenolic hydrogen (Kamal-Eldin & Appelqvist, 1996;Zigoneanu, Astete, & Sabliov, 2008). This compound may provide the beneficial effect of preventing chronic diseases associated with oxidative stress, such as cardiovascular disease, atherosclerosis and cancer (Brigelius-Flohe & Traber, 1999).…”

“…However, its applications are limited due to its sensitivity to heat, oxygen and light as well as its highly hydrophobic nature. Many efforts have been made to protect a-tocopherol from hostile environments and dissolve or disperse it in aqueous media through encapsulation technology (Yoo, Song, Chang, & Lee, 2006;Zigoneanu et al, 2008).…”

Physicochemical Properties and Control Release of Aloe Vera (Aloe barbadensis Miller) Bioactive Loaded Poly (Lactic Co-Glycolide Acid) Synthesized Nanoparticles

“…The PSD is influenced by the electrostatic repulsion between particles disperse in the liquid suspension, hence there is a strong correlation between the electrokinetic potential and PDI. A PDI value less than 0.1 indicates a homogenous and mono-dispersity and hence a better particle size distribution [15], and Qi et al [16] reported a zeta potential values of ±30 mV as a standard value for a stable nanoemulsion with less tendency for particle aggregation.…”