Ultrabright Green-Emitting Nanoemulsions Based on Natural Lipids-BODIPY Conjugates

Nanoemulsions (NEs) are water-dispersed oil droplets that constitute stealth biocompatible nanomaterials. NEs can reach an impressive degree of fluorescent brightness owing to their oily core that can encapsulate a large number of fluorophores on the condition the latter are sufficiently hydrophobic and oil-soluble. BODIPYs are among the brightest green emitting fluorophores and as neutral molecules possess high lipophilicity. Herein, we synthesized three different natural lipid-BODIPY conjugates by esterification of an acidic BODIPY by natural lipids, namely: α-tocopherol (vitamin E), cholesterol, and stearyl alcohol. The new BODIPY conjugates were characterized in solvents and oils before being encapsulated in NEs at various concentrations. The physical (size, stability over time, leakage) and photophysical properties (absorption and emission wavelength, brightness, photostability) are reported and showed that the nature of the lipid anchor and the nature of the oil used for emulsification greatly influence the properties of the bright NEs.

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Active motion of multiphase oil droplets: emergent dynamics of squirmers with evolving internal structure

Soft Matter ◽

10.1039/d0sm01873b ◽

2021 ◽

Author(s):

Xin Wang ◽

Rui Zhang ◽

Ali Mozaffari ◽

Juan J. de Pablo ◽

Nicholas L. Abbott

Keyword(s):

Internal Structure ◽

Oil Droplets ◽

Active Motion ◽

Over Time ◽

Emergent Dynamics

Self-propelled motions of active droplets can be programmed by transforming their internal morphologies over time.

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Research on Dispersed Oil Droplets Breakage and Emulsification in the Dynamic Oil and Water Hydrocyclone

Advance Journal of Food Science and Technology ◽

10.19026/ajfst.5.3215 ◽

2013 ◽

Vol 5 (8) ◽

pp. 1110-1116 ◽

Cited By ~ 5

Author(s):

Guangdong Guo ◽

Songsheng Deng

Keyword(s):

Oil Droplets ◽

Dispersed Oil

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OIL SPILL CLEANUP WITH DISPERSANTS: A BOOMED OIL SPILL EXPERIMENT

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-1981-1-263 ◽

1981 ◽

Vol 1981 (1) ◽

pp. 263-268

Author(s):

Joseph Buckley ◽

David Green ◽

Blair Humphrey

Keyword(s):

Water Column ◽

Oil Spill ◽

Oil Spills ◽

Sea Water ◽

Visual Observation ◽

Oil Droplets ◽

Oil Boom ◽

Dispersed Oil ◽

Vertical Density ◽

Oil Spill Cleanup

ABSTRACT Three experimental oil spills of 200, 400, and 200 litres (l) were conducted in October, 1978, in a semiprotected coastal area on Canada's west coast. The surface slicks were restrained with a Bennett inshore oil boom. The spilled oil was chemically dispersed using Corexit 9527, applied as a 10-percent solution in sea water and sprayed from a boat. The dispersed oil was monitored fluorometrically for some hours. Surface and dispersed oil were sampled for chemical analysis. The highest recorded concentration of dispersed oil was 1 part per million (ppm). After a short time (30 minutes), concentrations around 0.05 ppm were normal, decreasing to background within 5 hours. The concentrations were low compared to those expected for complete dispersion which, as visual observation confirmed, was not achieved. The dispersed oil did not mix deeper into the water column with the passage of time, in contrast to predicted behaviour and in spite of the lack of a significant vertical density gradient in the sea water. This was attributed to the buoyancy of the dispersed oil droplets and the limited vertical turbulence in the coastal locale of the experiment. The integrated quantity of oil in the water column decreased more rapidly than either the mean oil concentration of the cloud or the maximum concentration indicating that some of the dispersed oil was rising back to the surface. The surfacing of dispersed oil was confirmed visually during the experiment. The mixing action of the spray boat and breaker boards apparently created large oil droplets that did not form a stable dispersion. Horizontal diffusion of the dispersed oil was initially more rapid than expected, but the rate of spreading did not increase with time as predicted. The results imply that the scale of diffusion was larger than the scale of turbulence which again can be attributed to the locale of the experiment.

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A SAMPLER FOR THE COLLECTION OF DISPERSED OIL DROPLETS

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-1989-1-567 ◽

1989 ◽

Vol 1989 (1) ◽

pp. 567-568 ◽

Cited By ~ 2

Author(s):

Gerard A. L. Delvigne

Keyword(s):

Oil Droplets ◽

Dispersed Oil

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EFFECT OF MIXING ENERGY, MIXING TIME AND SETTLING TIME ON DISPERSION EFFECTIVENESS IN TWO BENCH-SCALE TESTING SYSTEMS

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2008-1-651 ◽

2008 ◽

Vol 2008 (1) ◽

pp. 651-656 ◽

Cited By ~ 2

Author(s):

Biplab Mukherjee

Keyword(s):

Energy Dissipation ◽

Size Distribution ◽

Mixing Time ◽

Tween 80 ◽

Settling Time ◽

Oil Droplets ◽

Mixing Energy ◽

Oil Dispersant ◽

Dissipation Rates ◽

Dispersed Oil

ABSTRACT Dispersion experiments were conducted in baffled-flask and paddle-jar mixing systems at five energy dissipation rates ranging from 4.8 × 10−4 to 1.6 × 10−1 J/kg-s. The objective of these experiments was to investigate the effects of mixing energy, mixing time, and settling time on dispersion effectiveness and size distribution of the chemically dispersed oil droplets. Two separate combinations of evaporatively weathered Mars crude oil premixed with dispersants differing in hydrophile-lipophile balance (HLB) (12 and 10) but having the same chemical composition (Tween 80 and Span 80 in dodecane) were used. Dispersion effectiveness increased with energy dissipation rate to a maximum and then leveled for all cases studied. In the baffled flask, dispersion effectiveness reached a maximum of 82 ± 5% irrespective of oil-dispersant combination. In the paddle jar, the maximum value of dispersion effectiveness was oil-dispersant specific, being at 87 ± 9% and 30 ± 11% for dispersant HLB 12 and 10, respectively. Mixing time did not seem to have a significant effect on dispersion effectiveness in comparison to the effects of energy dissipation rates and oil-dispersant combinations. The normalized volume distributions of the dispersed oil droplets were tri-modal in both systems, suggesting that multiple mechanisms of droplet formation occurred. The largest droplet mode disappeared from the size distribution in dispersions produced in the baffled flask when the mixing energy was >1.6 × 10−2 J/kg-s. A similar behavior was also observed in the paddle jar for the oil-dispersant combination of HLB 12, but not for HLB 10. Inclusion of a settling period of 20 minutes before collecting sample decreased the dispersion effectiveness in paddle jar but no significant changes were observed in the baffled flask system. The differences observed were due to the differences in the size distributions of the dispersed oil droplets generated in these two systems.

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Using a New Dispersed Oil Model to Support Ecological Risk Assessment

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2003-1-523 ◽

2003 ◽

Vol 2003 (1) ◽

pp. 523-530 ◽

Cited By ~ 3

Author(s):

Alan Mearns ◽

Glen Watabayashi ◽

Caitlin O'Connor

Keyword(s):

Risk Assessment ◽

Ecological Risk ◽

Ecological Risk Assessment ◽

Open Ocean ◽

The Other ◽

Ocean Water ◽

Moderate Risk ◽

Dispersed Oil ◽

Oil Concentration ◽

Over Time

ABSTRACT A new model is being used to support dispersant Ecological Risk Assessment (ERA) workshops. User-driven output includes trajectory maps for both chemically dispersed and undispersed oil, and concentration isopleths reported by depth and over time. To help make toxicological sense of the output, oil concentration isopleths were nominally fixed at concentrations and exposure times of concern developed by consensus during past ERA workshops. Two No. 6 fuel spill scenarios, each with alternative outcomes (not dispersed vs 80% dispersed) were developed, one in open ocean water (10,000 bbls spill), and the other in an estuary (2000 bbls spill). Plume epicenter maximum dispersed oil concentrations peaked in the range of 10–20 ppm but decreased within 24 hours to 1–2 ppm or less. Average concentrations in the most contaminated portions of the dispersion area never exceeded 3 ppm in either scenario. Plankton in a small (< 25%) fraction of the open ocean plume were at moderate risk at 24 hours. These effects must be compared to those of the non-dispersion alternative, which could impact wildlife and shorelines.

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Serum vitamin E decreases in HIV-seropositive subjects over time

Journal of Laboratory and Clinical Medicine ◽

10.1016/s0022-2143(97)90024-x ◽

1997 ◽

Vol 130 (3) ◽

pp. 293-296 ◽

Cited By ~ 22

Author(s):

Eric R Pacht ◽

Phil Diaz ◽

Tom Clanton ◽

Judy Hart ◽

James E Gadek

Keyword(s):

Vitamin E ◽

Serum Vitamin ◽

Hiv Seropositive ◽

Over Time

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Effects of Chemical Dispersant on the Surface Properties of Kaolin and Aggregation with Spilled Oil

10.21203/rs.3.rs-671319/v1 ◽

2021 ◽

Author(s):

Wenxin Li ◽

Yue Yu ◽

Deqi Xiong ◽

Zhixin Qi ◽

Sinan Fu ◽

...

Keyword(s):

Crude Oil ◽

Surface Properties ◽

Oil Spills ◽

Size Ratio ◽

Small Scale ◽

Oil Droplets ◽

Mineral Aggregate ◽

Chemical Dispersant ◽

Dispersed Oil ◽

Spilled Oil

Abstract After oil spills occur, dispersed oil droplets can collide with suspended particles in the water column to form the oil-mineral aggregate (OMA) and settle to the seafloor. However, only a few studies have concerned the effect of chemical dispersant on this process. In this paper, the mechanism by which dispersant affects the surface properties of kaolin as well as the viscosity and oil-seawater interfacial tension (IFTow) of Roncador crude oil were separately investigated by small scale tests. The results indicated that the presence of dispersant impairs the zeta potential and enhances the hydrophobicity of kaolin. The viscosity of Roncador crude oil rose slightly as the dosage of dispersant increased while IFTow decreased significantly. Furthermore, the oil dispersion and OMA formation at different dispersant-to-oil ratio (DOR) were evaluated in a wave tank. When DOR was less than 1:40, the oil enhancement of dispersant was not significant. In comparison, it began to contribute when DOR was over 1:40 and the effect became more pronounced with the increasing DOR. The adhesion between oil droplets and kaolin was inhibited with the increasing DOR. The size ratio between oil droplets and particles is the significant factor for OMA formation. The closer the oil-mineral size ratio is to 1, the more difficultly the OMA forms.

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