The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
David Julian Mcclements - One of the best experts on this subject based on the ideXlab platform.
-
Optimization of orange oil nanoemulsion formation by isothermal low-energy methods: Influence of the oil phase, surfactant, and temperature
Journal of Agricultural and Food Chemistry, 2014Co-Authors: Yuhua Chang, David Julian McclementsAbstract:Nanoemulsions are particularly suitable as a platform in the development of delivery systems for lipophilic functional agents. This study shows that transparent orange oil nanoemulsions can be fabricated using an isothermal low-energy method (spontaneous emulsification), which offers the advantage of fabricating flavor oil delivery systems using rapid and simple processing operations. Orange oil nanoemulsions were formed spontaneously by titration of a mixture of orange oil, carrier oil (medium chain triglyceride, MCT) and non-ionic surfactant (Tween) into an aqueous solution (5 mM citrate buffer, pH 3.5) with continuous stirring. The oil-to-emulsion ratio content was kept constant (10 wt%) while the surfactant-to-emulsion ratio (SER) was varied (2.5 to 20 wt%). Oil phase composition (orange oil to MCT), SER and surfactant type all had an appreciable effect on nanoemulsion formation and stability. Transparent nanoemulsions could be formed under certain conditions: 20% surfactant (Tween 40, Tween 60 or Tween 80) and 10% oil phase (4% to 6% orange oil + 6% to 4% MCT). Surfactant type and oil phase composition also affected the thermal stability of the nanoemulsions. Most of the nanoemulsions broke down after thermal cycling (20 ºC to 90 ºC to 20 ºC), however one system remained transparent after thermal cycling: 20% Tween 80, 5% orange oil, 5% MCT. The mean droplet size of these nanoemulsions increased over time, but the droplet growth rate was reduced appreciably after dilution. These results have important implications for the design and utilization of nanoemulsions as delivery systems in the food and other industries.
-
inhibition of lipase catalyzed hydrolysis of emulsified triglyceride oils by low molecular weight surfactants under simulated gastrointestinal conditions
European Journal of Pharmaceutics and Biopharmaceutics, 2011Co-Authors: Yan Li, David Julian McclementsAbstract:Abstract The effect of low-molecular weight surfactants on the digestibility of lipids in protein-stabilized corn oil-in-water emulsions was studied using an in vitro digestion model. The impact of non-ionic (Tween 20, Tween 80, Brij35), anionic (SDS), and cationic (DTAB) surfactants on the rate and extent of lipid digestion was studied. All surfactants were found to inhibit lipid digestion at sufficiently high concentrations, with half-maximal inhibitory concentrations (IC50) of 1.2% for Tween 20, 0.7% for Tween 80, 2.8% for Brij35, 1.1% for SDS, and 1.4% for DTAB. The effectiveness of the surfactants at inhibiting lipid digestion was therefore not strongly correlated to the electrical characteristics of the surfactant head group, since the IC50 increased in the following order: Tween 80 > SDS > Tween 20 > DTAB > Brij35. The ability of these low-molecular weight surfactants to inhibit lipid digestion was attributed to a number of potential mechanisms: (i) prevention of lipase/co-lipase adsorption to the oil–water interface; (ii) formation of interfacial complexes; (iii) direct interaction and inactivation of lipase/co-lipase. Interestingly, DTAB increased the rate and extent of lipid digestion when present at relatively low concentrations. This may have been because this cationic surfactant facilitated the adsorption of lipase to the droplet surfaces through electrostatic attraction, or it bound directly to the lipase molecule thereby changing its structure and activity. A number of the surfactants themselves were found to be susceptible to enzyme digestion by pancreatic enzymes in the absence of lipids: Tween 20, Tween 80, Brij35, and DTAB. This work has important implications for the development of emulsion-based delivery systems for food and pharmaceutical applications.
-
Impact of tween 20 hydroperoxides and iron on the oxidation of methyl linoleate and salmon oil dispersions.
Journal of Agricultural and Food Chemistry, 2001Co-Authors: Nuchi Cd, David Julian Mcclements, Eric A. DeckerAbstract:To determine the role of surfactant hydroperoxides on the oxidative stability of fatty acids, the oxidation of methyl linoleate micelles and salmon oil-in-water emulsions was measured as a function of varying Tween 20 hydroperoxide concentrations. Increasing Tween 20 hydroperoxide concentrations from 3.5 to 14.7 μmol hydroperoxide/g Tween 20 decreased the lag phase of headspace hexanal formation but did not increase the total amount of hexanal formed in methyl linoleate/Tween 20 micelles. In the micelle system, Fe2+ decreased the lag phase of hexanal formation but increased total hexanal concentrations only in micelles with the highest Tween 20 hydroperoxide concentrations (14.7 μmol hydroperoxide/g surfactant). Increasing Tween 20 surfactant hydroperoxide concentrations also increased the oxidation of salmon oil-in-water emulsions as determined by lipid hydroperoxides and headspace propanal. In both the micelle and emulsion systems, the prooxidant effect of Fe2+ decreased with increasing Tween 20 hydrope...
Patrick Garidel - One of the best experts on this subject based on the ideXlab platform.
-
Albumin displacement at the air–water interface by Tween (Polysorbate) surfactants
European Biophysics Journal, 2020Co-Authors: Martin Rabe, Andreas Kerth, Alfred Blume, Patrick GaridelAbstract:Tween (polysorbate) 20 and 80 are surfactants used for the development of parenteral protein drugs, due to their beneficial safety profile and stabilisation properties. To elucidate the mechanism by which Tween 20 and 80 stabilise proteins in aqueous solutions, either by a “direct” protein to surfactant interaction and/or by an interaction with the protein film at the air–water interface, we used spectroscopic (Infrared Reflection Absorption Spectroscopy, IRRAS) and microscopic techniques (Brewster Angle Microscopy, BAM) in combination with surface pressure measurements. To this end, the impact of both types of Tweens with regard to the displacement of the protein from the air–water interface was studied. As a model protein, human serum albumin (HSA) was used. The results for the displacement of the adsorbed HSA films by Tweens 20 and 80 can partially be understood on the basis of an orogenic displacement mechanism, which depends on the critical surface pressure of the adsorbed protein film. With increasing concentration of Tween in the sub-phase, BAM images showed the formation of different domain morphologies. IRRA-spectra supported the finding that at high protein concentration in the sub-phase, the protein film could not be completely displaced by the surfactants. Comparing the impact of both surfactants, we found that Tween 20 adsorbed faster to the protein film than Tween 80. The adsorption kinetics of both Tweens and the speed of protein displacement increased with rising surfactant concentration. Tween 80 reached significant lower surface pressures than Tween 20, which led to an incomplete displacement of the observed HSA film.
Qixin Zhong - One of the best experts on this subject based on the ideXlab platform.
-
Lemon oil nanoemulsions fabricated with sodium caseinate and Tween 20 using phase inversion temperature method
Journal of Food Engineering, 2016Co-Authors: Dan Su, Qixin ZhongAbstract:Abstract The phase inversion temperature (PIT) method has been studied to fabricate nanoemulsions using non-ionic synthetic surfactants, but not food biopolymers. The objective of this study was to investigate the PIT formation of lemon oil nanoemulsions by combinations of Tween 20 and sodium caseinate (NaCas). The emulsions prepared with combinations of NaCas and Tween 20 had lower turbidity and smaller droplets than those prepared with one surfactant, and the co-adsorption of NaCas on oil droplets decreased with increasing Tween 20 concentration. Negative and positive impacts on nanoemulsion formation were observed at 0.2–0.4 and 0.6–0.8 mM NaCl, respectively. Turbidity and rheology results showed the PIT between 80 and 90 °C. The nanoemulsions prepared with 2% NaCas, 0.4–1.2% Tween 20 and 1.5% lemon oil had a volume-area mean diameter of around 100 nm and were stable during 15-day storage. Therefore, NaCas can be used to partially replace synthetic surfactants to prepare flavor oils nanoemulsions using the PIT method.
-
microemulsions based on a sunflower lecithin tween 20 blend have high capacity for dissolving peppermint oil and stabilizing coenzyme q10
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Huaiqiong Chen, Yongguang Guan, Qixin ZhongAbstract:The objectives of the present study were to improve the capability of microemulsions to dissolve peppermint oil by blending sunflower lecithin with Tween 20 and to study the possibility of codelivering lipophilic bioactive compounds. The oil loading in microemulsions with 20% (w/w) Tween 20 increased from 3% (w/w) to 20% (w/w) upon gradual supplementation of 6% (w/w) lecithin. All microemulsions had particles of <12 nm that did not change over 70 d of storage at 21 °C. They had relatively low Newtonian viscosities and were physically and chemically stable after 50–200-fold dilution in water, resulting from similar hydrophile–lipophile-balance values of the surfactant mixture and peppermint oil. Furthermore, the microemulsions were capable of dissolving coenzyme Q10 and preventing its degradation at UV 302 nm, more significant for the microemulsion with lecithin. Therefore, natural surfactant lecithin can reduce the use of synthetic Tween 20 to dissolve peppermint oil and protect the degradation of dissolv...
-
In vitro release kinetics of nisin as affected by Tween 20 and glycerol co-encapsulated in spray-dried zein capsules
Journal of Food Engineering, 2011Co-Authors: Dan Xiao, Qixin ZhongAbstract:Delivery systems with sustained release of antimicrobials have been proposed to improve long-term effectiveness of antimicrobials in foods. In this work, we studied the effect of Tween 20 and glycerol in spray-drying formulations on resultant microstructures of zein capsules and release profiles of encapsulated nisin. Tween 20 and glycerol changed capsules from a continuous matrix to shell-type structures. All samples showed complete release of nisin in 30 min at pH 2.0. Capsules with a higher amount of Tween 20 showed more complete release of nisin at pH 8.0, in contrast to no apparent impact by glycerol. Addition of 0.05% Tween 20 or glycerol in the feed both reduced the burst release of nisin at pH 6.0, but no conclusive trends were observed for the impact of their usage levels. Our work showed that an appropriate formulation is needed to obtain desirable delivery systems of antimicrobials such as nisin.
Veljko Krstonosic - One of the best experts on this subject based on the ideXlab platform.
-
interactions between sodium cholate or sodium deoxycholate and nonionic surfactant tween 20 or tween 60 in aqueous solution
Industrial & Engineering Chemistry Research, 2012Co-Authors: Dejan Cirin, Mihalj Posa, Veljko KrstonosicAbstract:Knowledge of physicochemical parameters of mixed micelles is important in order to develop drug delivery systems with required characteristics. Investigated bile salts and Tweens are relatively nontoxic surfactants, extensively studied as biocompatible colloidal drug carriers. The micellization behavior of binary anionic–nonionic surfactant mixtures built of sodium cholate or sodium deoxycholate and one of two Tweens (Tween 20 or Tween 60) was investigated by conductivity and surface tension measurements. The results of the study have been analyzed using Clint’s, Rubingh’s, and Motomura’s theories for mixed binary systems. The determined physicochemical properties, particularly the negative values of the interaction parameter, indicate synergism between the individual surfactants in the mixed micelles. It was noticed that Tween with a longer hydrophobic tail shows stronger interactions with selected bile salts. However, it was found that the more hydrophilic bile salt (sodium cholate) generates the strong...
N H Ayachit - One of the best experts on this subject based on the ideXlab platform.
-
ultrasonic study of thermo acoustic parameters of the polysorbate 20 40 60 and 80 liquid surfactants at different temperatures
Journal of Molecular Liquids, 2014Co-Authors: F M Sannaningannavar, Shivaram N Patil, R M Melavanki, B S Navati, N H AyachitAbstract:Abstract Ultrasonic velocities (u) and densities (ρ) have been measured at different temperatures ranging from 298 K to 353 K for non-ionic (NIC) surfactants like polyoxyethylene (20) sorbitan monolaurate (Tween-20), polyoxyethylene (20) sorbitan palmitate (Tween-40), polyoxyethylene (20) sorbitan monostearate (Tween-60) and polyoxyethylene (20) sorbitan monooleate (Tween-80). From these isentropic compressibility (β), intermolecular free length (Lf), acoustic impedance (Z), molar volume (V), available volume (Va), molar sound velocity (Ra) and molar compressibility (W) have been calculated. The focuses on the review of the chemical structure of polysorbates and the influence of the temperature on acoustical parameters have been employed to discuss molecular packing, molecular movement, structure alterations and molecular interactions.
