Background: Palm oil esters (POEs) are esters derived from palm oil and oleyl alcohol have great potential in the\r\ncosmetic and pharmaceutical industries due to the excellent wetting behavior of the esters without the oily feel.\r\nThe role of oil-in-water nanoemulsions loaded with tocotrienol sedimentation behavior was studied. LUMiFugeÃ?®\r\n116 particle separation analyzer was used to investigate the sedimentation behavior of POEs/tocotrienol/xanthan\r\ngum nanoemulsion system during centrifugation. Analyzing the sedimentation kinetics of dispersions in a\r\ncentrifugal field also yields information about the rheological behavior and structural stability.\r\nMethods: Experiments were performed in an analytical centrifuge at 11Ã?â??g to 1140Ã?â??g (LUMiFugeÃ?® 116 particle\r\nseparation analyzer). The samples in the LUMiFugeÃ?® 116 particle separation analyzer were centrifuged at 3000 rpm\r\nfor 15 h at 32Ã?°C. Sample volume of 2 cm3 was used. The rheological property of nanoemulsions was investigated\r\nusing oscillatory measurements test. A rotational/oscillatory viscometer, Kinexus Rheometer (Malvern Instrument,\r\nUK) was used. All measurements were performed with a stainless steel cone-plate sensor at 25.0 Ã?± 0.1Ã?°C with\r\n4Ã?°/40 mm.\r\nResults: The stable nanoemulsions showed sedimentation rates at earth gravity of 5.2, 3.0 and 2.6 mm/month for\r\n10%, 20% and 30% (w/w) oil phase, respectively. Rheological behavior is an important target during the design of\r\npalm oil esters-based nanocosmeceuticals. The presence of a network structure was indicated by measurements\r\nwhich showed Gââ?¬â?¢ to be greater than Gââ?¬Â. This result implied the predominant elastic response and high storage\r\nstability of the nanoemulsion. It was also observed that the increase in oil phase concentration led to the profile\r\nwhich strongly indicated that the solid like elastic property; where the values of phase angle, d of these\r\nnanoemulsions was lower than 45Ã?°.\r\nConclusions: The nanoemulsions with higher oil phase concentration (30% (w/w)) showed greater elasticity which\r\nimplied strong dynamic rigidity of the nanoemulsion. It was the most stable with longest shelf-life.
Loading....