Comprehensive study of α-terpineol-loaded oil-in-water (O/W) nanoemulsion: interfacial property, formulation, physical and chemical stability

AbstractIn this study, the interfacial ability of α-terpineol (α-TOH) was reported, followed by its trapping into oil-in-water (O/W) nanoemulsion as active-ingredient and the long-term observation of this nanosystem influenced by the storage-time (410-days) and temperature (5, 25, 50 °C). The results indicated that the α-TOH can reduce the interfacial tension on the liquid-liquid interface (ΔG°m = −1.81 KJ mol−1; surface density = 8.19 × 10−6 mol m−2; polar head group area = 20.29 Å2), in the absence or presence of surfactant. The O/W nanoemulsion loaded with a high amount of α-TOH (90 mg mL−1; 9α-TOH-NE) into the oil phase was successfully formulated. Among the physical parameters, the mean droplet diameter (MDD) showed a great thermal dependence influenced by the storage-temperature, where the Ostwald ripening (OR) was identified as the main destabilizing phenomena that was taking place on 9α-TOH-NE at 5 and 25 °C along with time. Despite of the physical instability, the integrity of both nanoemulsion at 5 °C and 25 °C was fully preserved up to 410th day, displaying a homogeneous and comparable appearance by visual observation. On contrary, a non-thermal dependence was found for chemical stability, where over 88% of the initial amount of the α-TOH nanoemulsified remained in both 9α-TOH-NE at 5 and 25 °C, up to 410th day. Beyond the key data reported for α-TOH, the importance of this research relies on the long-term tracking of a nanostructured system which can be useful for scientific community as a model for a robust evaluation of nanoemulsion loaded with flavor oils.

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Hydrothermic Treatment Effects on Some Ripening Changes on Mango Fruits (Mangifera indica L) Crillo de Bocado' during Storage: I. Physical Parameters

HortScience ◽

10.21273/hortsci.33.3.520d ◽

1998 ◽

Vol 33 (3) ◽

pp. 520d-520

Author(s):

Oswaldo Valor ◽

Juan E Manzano

Keyword(s):

Weight Loss ◽

Skin Color ◽

Storage Temperature ◽

Mangifera Indica ◽

Physical Parameters ◽

Fresh Weight ◽

Randomized Design ◽

High Storage Temperature ◽

High Storage ◽

Green Stage

Mango fruits `Criollo de Bocado' harvested at the mature-green stage were treated with a hydrothermic treatment of 55 °C for 3 min and stored for 20 days to temperatures of 10 ± 2, 15 ± 2, and 28 ± 2 °C. A randomized design 2 × 3 × 4 with three replications was used. Physical parameters such as color (L*, a*, b*), firmnness, and fresh weight loss were studied. Results reported that mango fruits stored at 10.2 and 15.2 °C showed the highest firmness values. Skin color changed very fast during the first storage days, while pulp color required more time to achieve mature ripe color. Fresh weight loss tended to increase with storage time and with high storage temperature. The lowest storage temperture retarded softening in mango fruits and firmnness reached the highest values.

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Chemical stability of oil-infused polyethylene

Journal of Biomaterials Applications ◽

10.1177/0885328220977353 ◽

2020 ◽

pp. 088532822097735

Author(s):

Fedra P Zaribaf ◽

Harinderjit S Gill ◽

Elise C Pegg

Keyword(s):

Vitamin E ◽

Chemical Stability ◽

Antioxidant Properties ◽

Oxidation Stability ◽

Thermal Ageing ◽

Similar Process ◽

Mechanical Degradation ◽

Suitable Material ◽

Thermally Treated

Ultra-high molecular weight polyethylene (UHMWPE) can be made radiopaque for medical imaging applications through the diffusion of an iodised oil-based contrast agent (Lipiodol Ultra Fluid). A similar process is used for Vitamin E incorporated polyethylene which provides antioxidant properties. This study aimed to investigate the critical long-term properties of oil-infused medical polyethylene after 4 weeks of accelerated thermal ageing. Samples treated with an oil (Vitamin E or Lipiodol) had a higher oxidation stability than currently used medical grade polyethylene, indicated by a smaller increase in oxidation index after ageing (Vitamin E + 36%, Lipiodol +40%, Untreated +136%, Thermally treated +164%). The tensile properties of oil treated polyethylene after ageing were significantly higher than the Untreated and Thermally treated controls (p<0.05) indicating less mechanical degradation. There was also no alteration in the percentage crystallinity of oil treated samples after ageing, though the radiopacity of the Lipiodol treated samples reduced by 54% after ageing. The leaching of oil with time was also investigated; the leaching of Lipiodol and Vitamin E followed the same trend and reached a steady state by two weeks. Overall, it can be concluded that the diffusion of an oil-based fluid into polyethylene not only increases the oxidative and chemical stability of polyethylene but also adds additional functionality (e.g. radiopacity) providing a more suitable material for long–term medical applications.

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Parenteral Nutrition and Oxidant Load in Neonates

Nutrients ◽

10.3390/nu13082631 ◽

2021 ◽

Vol 13 (8) ◽

pp. 2631

Author(s):

Kandeepan Karthigesu ◽

Robert F. Bertolo ◽

Robert J. Brown

Keyword(s):

Parenteral Nutrition ◽

Storage Temperature ◽

Oral Feeding ◽

Published Data ◽

Short Term ◽

Antioxidant Defences ◽

Term Survival ◽

Nutrient Sources ◽

Short Term Survival

Neonates with preterm, gastrointestinal dysfunction and very low birth weights are often intolerant to oral feeding. In such infants, the provision of nutrients via parenteral nutrition (PN) becomes necessary for short-term survival, as well as long-term health. However, the elemental nutrients in PN can be a major source of oxidants due to interactions between nutrients, imbalances of anti- and pro-oxidants, and environmental conditions. Moreover, neonates fed PN are at greater risk of oxidative stress, not only from dietary sources, but also because of immature antioxidant defences. Various interventions can lower the oxidant load in PN, including the supplementation of PN with antioxidant vitamins, glutathione, additional arginine and additional cysteine; reduced levels of pro-oxidant nutrients such as iron; protection from light and oxygen; and proper storage temperature. This narrative review of published data provides insight to oxidant molecules generated in PN, nutrient sources of oxidants, and measures to minimize oxidant levels.

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Long-Term Stability of Different Kinds of Gas Nanobubbles in Deionized and Salt Water

Materials ◽

10.3390/ma14071808 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1808

Author(s):

Yali Zhou ◽

Zhenyao Han ◽

Chunlin He ◽

Qin Feng ◽

Kaituo Wang ◽

...

Keyword(s):

Aqueous Solution ◽

Bubble Size ◽

Ostwald Ripening ◽

Salt Water ◽

Dlvo Theory ◽

Deionized Water ◽

Hydrodynamic Cavitation ◽

Term Stability ◽

Long Term Stability

Nanobubbles have many potential applications depending on their types. The long-term stability of different gas nanobubbles is necessary to be studied considering their applications. In the present study, five kinds of nanobubbles (N2, O2, Ar + 8%H2, air and CO2) in deionized water and a salt aqueous solution were prepared by the hydrodynamic cavitation method. The mean size and zeta potential of the nanobubbles were measured by a light scattering system, while the pH and Eh of the nanobubble suspensions were measured as a function of time. The nanobubble stability was predicted and discussed by the total potential energies between two bubbles by the extended Derjaguin–Landau–Verwey–Overbeek (DLVO) theory. The nanobubbles, except CO2, in deionized water showed a long-term stability for 60 days, while they were not stable in the 1 mM (milli mol/L) salt aqueous solution. During the 60 days, the bubble size gradually increased and decreased in deionized water. This size change was discussed by the Ostwald ripening effect coupled with the bubble interaction evaluated by the extended DLVO theory. On the other hand, CO2 nanobubbles in deionized water were not stable and disappeared after 5 days, while the CO2 nanobubbles in 1 mM of NaCl and CaCl2 aqueous solution became stable for 2 weeks. The floating and disappearing phenomena of nanobubbles were estimated and discussed by calculating the relationship between the terminal velocity of the floating bubble and bubble size.

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Modulation of casein kinase II activity by the polar head group of an insulin-sensitive glycosyl-phosphatidylinositol.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)34051-7 ◽

1990 ◽

Vol 265 (9) ◽

pp. 4849-4852

Author(s):

S Alemany ◽

J Puerta ◽

A Guadaño ◽

J M Mato

Keyword(s):

Casein Kinase Ii ◽

Casein Kinase ◽

Head Group ◽

Polar Head Group ◽

Glycosyl Phosphatidylinositol ◽

Polar Head

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Nanoemulsions for the Encapsulation of Hydrophobic Actives

Cosmetics ◽

10.3390/cosmetics8020045 ◽

2021 ◽

Vol 8 (2) ◽

pp. 45

Author(s):

Eduardo Guzmán ◽

Laura Fernández-Peña ◽

Lorenzo Rossi ◽

Mathieu Bouvier ◽

Francisco Ortega ◽

...

Keyword(s):

Surface Charge ◽

Long Term Stability ◽

Promising Tool ◽

Oil In Water ◽

Nanometric Range ◽

Negative Surface ◽

Negative Surface Charge ◽

Highly Hydrophobic ◽

Technological Interest

This work analyzes the dispersion of two highly hydrophobic actives, (9Z)-N-(1,3-dihydroxyoctadecan-2-yl)octadec-9-enamide (ceramidelike molecule) and 2,6-diamino-4-(piperidin-1-yl)pyrimidine 1-oxide (minoxidil), using oil-in-water nanoemulsions with the aim of preparing stable and safe aqueous-based formulations that can be exploited for enhancing the penetration of active compounds through cosmetic substrates. Stable nanoemulsions with a droplet size in the nanometric range (around 200 nm) and a negative surface charge were prepared. It was possible to prepare formulations containing up to 2 w/w% of ceramide-like molecules and more than 10 w/w% of minoxidil incorporated within the oil droplets. This emulsions evidenced a good long-term stability, without any apparent modification for several weeks. Despite the fact that this work is limited to optimize the incorporation of the actives within the nanoemulsion-like formulations, it demonstrated that nanoemulsions should be considered as a very promising tool for enhancing the distribution and availability of hydrophobic molecules with technological interest.

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Long-Term Structural and Chemical Stability of Carbon Electrodes in Vanadium Redox Flow Battery

ACS Applied Energy Materials ◽

10.1021/acsaem.1c00912 ◽

2021 ◽

Author(s):

Bhuvaneswari M. Sivakumar ◽

Venkateshkumar Prabhakaran ◽

Kaining Duanmu ◽

Edwin Thomsen ◽

Brian Berland ◽

...

Keyword(s):

Chemical Stability ◽

Vanadium Redox Flow Battery ◽

Carbon Electrodes ◽

Redox Flow Battery ◽

Flow Battery ◽

Vanadium Redox

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Molecular dynamics simulations and experimental studies reveal differential permeability of withaferin-A and withanone across the model cell membrane

Scientific Reports ◽

10.1038/s41598-021-81729-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Renu Wadhwa ◽

Neetu Singh Yadav ◽

Shashank P. Katiyar ◽

Tomoko Yaguchi ◽

Chohee Lee ◽

...

Keyword(s):

Molecular Dynamics ◽

Cell Membrane ◽

Molecular Dynamics Simulations ◽

Experimental Studies ◽

Bilayer Membrane ◽

Withaferin A ◽

Head Group ◽

Polar Head Group ◽

Natural Drugs ◽

Dynamics Simulations

AbstractPoor bioavailability due to the inability to cross the cell membrane is one of the major reasons for the failure of a drug in clinical trials. We have used molecular dynamics simulations to predict the membrane permeability of natural drugs—withanolides (withaferin-A and withanone) that have similar structures but remarkably differ in their cytotoxicity. We found that whereas withaferin-A, could proficiently transverse through the model membrane, withanone showed weak permeability. The free energy profiles for the interaction of withanolides with the model bilayer membrane revealed that whereas the polar head group of the membrane caused high resistance for the passage of withanone, the interior of the membrane behaves similarly for both withanolides. The solvation analysis further revealed that the high solvation of terminal O5 oxygen of withaferin-A was the major driving force for its high permeability; it interacted with the phosphate group of the membrane that led to its smooth passage across the bilayer. The computational predictions were tested by raising and recruiting unique antibodies that react to withaferin-A and withanone. The time-lapsed analyses of control and treated cells demonstrated higher permeation of withaferin-A as compared to withanone. The concurrence between the computation and experimental results thus re-emphasised the use of computational methods for predicting permeability and hence bioavailability of natural drug compounds in the drug development process.

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