Artificial Emulsion Research Articles

Production of artificial fingermarks. Part II – The use of a modified inkjet printer for the deposition of synthetic secretions

This study is the second part of a larger body of research dedicated to the production of synthetic secretions and the use of an inkjet printer to deposit realistic artificial fingermarks. An artificial emulsion combining eccrine and sebaceous compounds, which was described and tested in the first part of this research, was used as it showed a promising compatibility with common detection techniques. An inkjet printer was modified to print the emulsion on two different substrates: paper (porous) and acetate (non-porous). After optimisation of the printing parameters, multiple fingermarks were printed and processed with a range of standalone detection techniques: 1,2-indanedione-zinc, ninhydrin, Oil Red O, and physical developer on paper, and cyanoacrylate fuming, rhodamine 6G, gold/zinc vacuum metal deposition, and silver black powder on acetate. The detection techniques were also applied in sequence, which is considered one of the biggest advantages of the emulsion over simpler amino acid mixtures that are usable with amino acid reagents only. Natural fingermarks deposited by a single donor were processed with the same techniques for comparison. The effect of water immersion was also investigated, where fingermarks printed on paper were immersed in water for 15 min, before being processed with 1,2-indanedione-zinc and Oil Red O. The results showed that realistic-looking fingermarks could be printed on paper and that printing on acetate was also possible albeit of lower quality due to the nature of the substrate. The artificial fingermarks were successfully enhanced by all the detection techniques tested, at the notable exception of physical developer. The results obtained were very similar to what is generally observed with real fingermarks, and it was observed that the impact of water immersion on the artificial fingermarks was comparable as well. These findings open new perspectives for the development of multi-target quality control test strips or for the standardisation of proficiency testing and interlaboratory collaborative exercises where ground truth is crucial to guarantee comparable results and objective assessment.

Laboratory studies of physico-chemical methods to break emulsions stabilized with surfactant-polymer cocktails

Introduction. Oil field treatment often makes it necessary to combine different methods of well production treatment, taking into account the development regimes and parameters, produced and injected fluids, technical equipment and economic feasibility. The carried-out complex of laboratory tests is aimed at the creation and subsequent destruction of model systems with specified parameters. The list of the considered methods and the temperature regime of the tests are due to the physicochemical parameters and the field specifics. The purpose of this article is to search for an effective method for the primary treatment of well production after SP-flooding — a highly stable oil-water emulsion, additionally stabilized during pumping by means of an ESP. 
 
 Materials and methods. The laboratory tests helped to develop an optimal mode of creating an artificial emulsion based on oil from BS10-1 reservoir of the Kholmogorsk field in the Yamalo-Nenets Autonomous Okrug, and a surfactant-polymer cocktail, which simulates well production after SP-flooding. The research tested physicochemical methods of destroying oil-water emulsions, such as their dilution with formation fluids, thermal settling, gravitational separation by centrifugation at RPM = 4000–12000 rpm, introduction of demulsifiers, as well as a combined effect, including all of the above approaches. The tested methods were supplied with the calculated values of the oil phase final water-cut, which allowed us to evaluate the effectiveness of the applied approaches to the destruction of model systems. 
 
 Results. It has been found that not all of the applied approaches provide the extraction of the estimated amount of oil from emulsion systems with varying degrees of dilution by formation fluids. Satisfactory destruction of the emulsion was achieved after 10–20 min of centrifugation at T = 40 °C and RPM within 4000–8000 rpm. The traditional introduction of industrial demulsifiers into the studied systems without additional influences is ineffective. 
 
 Conclusion. The optimal level of water cut in the oil phase of ≤5% was achieved after diluting the emulsion with formation fluids, with a combined approach to the destruction of the original and diluted emulsion with formation fluids. In addition, the research showed that it is possible to re-use the extracted SP-composition when controlling its physicochemical parameters, taking into account the effect of the introduced additives.

Crown Ether‐Functionalized Complex Emulsions as an Artificial Adaptive Material Platform

AbstractResponsive materials capable of autonomously regulating and adapting to molecular recognition‐induced chemical events hold great promise in the design of artificial chemo‐intelligent life‐like soft material platforms. In this context, the design of a synthetically minimal artificial emulsion platform that, regulated by interfacial supramolecular recognition events, is capable to autonomously and reversibly adapt to its chemical environment is reported. The systems exhibit programmed up‐ and down‐regulating capabilities that are realized via selective assembly of synthesized crown ether surfactants onto one hemisphere of anisotropic biphasic emulsion droplets. Dynamic and reversible interfacial host–guest complexation of, for example, metal and ammonium ions or amino acids transduce into interface‐triggered morphological reconfigurations of the complex emulsion droplets, which mediate their ability to selectively present, hide, or expand liquid–liquid interfaces. The separate responsive modalities are then used to showcase the utility of such adaptive soft material platforms for a self‐regulated uptake and release of metal ions or phase‐transfer catalysts, a biomimetic recognition of biomolecules including amino acids, carbohydrates, and antibodies, and for triggered surface‐encoded payload release applications.

Study of the composition and properties of crude oil mined at the Ichyodinskoye field

This study was aimed at investigating the chemical composition and commercial properties of crude oil mined at the Ichyodinskoye field. A graph of atmospheric distillation was constructed. The content of commercial fractions was determined from the curve of true boiling temperatures. The obtained data were analysed according to the hydrocarbon composition of the gasoline fraction, which was found to comprise alkane, cycloalkane and aromatic compounds in the amount of 53.12%, 27.21% and 18.45%, respectively. In terms of sulphur, the oil mined at the Ichyodinskoye field is considered to be low-sulphur, thus belonging to the1st class. A distinctive feature of this oil consists in its inability to form stable emulsions due to a low content of solid paraffins in its composition. In the study, artificial emulsions of the oil and deposit water with a watercut value of 30% were obtained. The developed emulsions were investigated by analysing the process of gravitational settling for 120 min at a temperature of 50 °C, as well as using a LUMiFuge device. It was found that the oil mined at the Ichyodinskoye field is low-sulphur and light, containing a high content of light distillates. It is known that low-sulphur oils are safer for field equipment in terms of corrosion, thereby decreasing costs of supplying oil to consumers. Such oils are a high-quality and promising raw material for the production of oil products.

Selection of demulsifiers for transportation and oil preparation at Kondinskoye oil field

The article considers the results of the study on the selection of chemical reagents to improve the rheological properties of the oil emulsion of the Kondinskoye oil field during transportation and dehydration of the emulsion. The studies have been carried out on an artificial emulsion. We describe a method of determining demulsifying activity of a reagent at a certain temperature mode of a preliminary water discharge plant. In addition, we give the results of the study with various chemical reagents, select the optimal mode of emulsion preparation. This experiment was conducted in order to select the most effective demulsifiers to improve the technology and economics of the field and transportation process. The optimal choice of type of demulsifier, mode of its application and places of entry guarantee high quality of oil preparation. The following demulsifiers could be used in the process: DE-4, DE-6, and DE-9. The result of using these reagents is an optimal reagent flow rate per ton of fluid and a maximum amount of water separated from the emulsion over a certain time.

The artificial simulation of oilwater emulsions to study emulsion settling process with the use of coalescing element

The article presents the sequence and results of experimental modeling of artificial oil-water emulsions based on anhydrous oil and water with density and mineralization as close as possible to the real field conditions of the researched deposits. The practical importance of simulation of artificial emulsions was due to the need to work with emulsions of different degrees of water cut, which is possible only by laboratory simulation conditions. We prepared artificial oil-water emulsion using a turbine mixer in a thermostated container. Then we set the emulsion preparation mode: number of revolutions (n1, min –1) and mixing time (t, min). We selected the optimal parameters to create stable artificial oil-water emulsions according to different types of oils.

Plasma clearance of chylomicron remnants is delayed in aged subjects: A study with artificial emulsions

Plasma clearance of chylomicron remnants is delayed in aged subjects: A study with artificial emulsions

Saturated fatty acid in the phospholipid monolayer contributes to the formation of large lipid droplets

The degree of saturation of fatty acid chains in the bilayer membrane structure is known to control membrane fluidity and packing density. However, the significance of fatty acid composition in the monolayers of lipid droplets (LDs) has not been elucidated. In this study, we noted a relationship between the size of LDs and the fatty acid composition of the monolayer. To obtain large LDs, we generated NIH3T3 cells overexpressing fat-specific protein 27 (FSP27). This induced the fusion of LDs, resulting in larger LDs in FSP27-overexpressing cells compared with LDs in control cells. Moreover, the lipid extracts of LDs from FSP27-overexpressing cells reconstituted large-droplet emulsions in vitro, implying that the lipid properties of LDs might affect the size of LDs. FSP27-overexpressing cells had more saturated fatty acids in the phospholipid monolayer of the LDs compared with control cells. To further investigate the effects of the degree of phospholipid unsaturation on the size of LDs, we synthesized artificial emulsions of a lipid mixed with distearoylphosphatidylcholine (DSPC, diC18:0-PC) and with dioleoylphosphatidylcholine (DOPC, diC18:1n-9-PC) and compared the sizes of the resulting LDs. The emulsions prepared from saturated PC had larger droplets than those prepared from unsaturated PC. Our results suggest that saturated fatty acid chains in phospholipid monolayers might establish the form and/or stability of large LDs.

Oil and Water Separation Using a Glass Microfiber Coalescing Bed

A vertical sleeve separator using glass microfiber with a mean diameter of 4 µm as coalescence medium was explored to remove oil from the oil-in-water (O/W) emulsions. The artificial emulsions were prepared by mixing diesel oil and water to obtain oil droplets with a mean diameter about 7 µm. A series of experiments were performed to investigate the effect of such parameters as bed porosity (0.850–0.925), bed height (2.0–20.0 mm), flow velocity (1.0–20.0 mL/s), and influent oil concentration (200.0–3000.0 mg/L) on the effluent oil concentration and oil removal efficiency. The obtained effluent oil concentration was from 4.98 to 53.04 mg/L, and the oil removal efficiency was 96.4–99.8%. In addition, the article identifies the interaction between bed porosity and height, explains the mutual influences between the emulsion velocity and concentration, and quantitatively derives the appropriate ranges of bed characteristics and operating conditions.

The removal from plasma of chylomicrons and remnants is reduced in heterozygous familial hypercholesterolemia subjects with identified LDL receptor mutations: Study with artificial emulsions

Chylomicron remnants bind to both their specific receptors (LRP) and to the LDL receptor (LDLR) in the liver. There is controversy whether disturbances of chylomicron metabolism occur in subjects with familial hypercholesterolemia (FH). The aim of this study was to evaluate whether there are defects on the removal from plasma of chylomicrons and their remnants in heterozygous FH patients with determined LDLR mutations. We studied 20 heterozygous FH patients (43.2±12 years old, 60% males) and 50 normolipidemic subjects matched for age and gender. FH subjects were not in use of LDL-lowering drugs for at least 6 weeks. The removal from plasma of chylomicrons and their remnants was measured by isotopic decay after venous injection of a chylomicron-like emulsion radiolabeled with 14C-cholesteryl ester (14C-CE) and 3H-triolein (3H-TO). These track respectively removal from plasma of chylomicrons and remnants and lipolysis. There was a significant reduction in the fractional catabolic rates (FCR in h−1) of 14C-CE in FH in comparison with normolipidemics: 0.048 (1.46.10−7; 0.57) vs. 0.71(0.049; 1.62), [median (25th–75th percentile)], p=0.003. No differences were found in FCR of 3H-TO between FH and controls, respectively 1.62 (1.02; 2.331) and 1.914 (1.34; 2.878), p=0.405. In conclusion heterozygous FH subjects had a significant decrease on the removal from plasma of chylomicrons and their remnants compared with normolipidemics.

Metabolism of a Lipid Nanoemulsion Resembling Low-Density Lipoprotein in Patients with Grade III Obesity

INTRODUCTION:Obesity increases triglyceride levels and decreases high-density lipoprotein concentrations in plasma. Artificial emulsions resembling lipidic plasma lipoprotein structures have been used to evaluate low-density lipoprotein metabolism. In grade III obesity, low density lipoprotein metabolism is poorly understood.OBJECTIVE:To evaluate the kinetics with which a cholesterol-rich emulsion (called a low-density emulsion) binds to low-density lipoprotein receptors in a group of patients with grade III obesity by the fractional clearance rate.METHODS:A low-density emulsion was labeled with [14C]-cholesterol ester and [3H]-triglycerides and injected intravenously into ten normolipidemic non-diabetic patients with grade III obesity [body mass index higher than 40 kg/m2] and into ten non-obese healthy controls. Blood samples were collected over 24 hours to determine the plasma decay curve and to calculate the fractional clearance rate.RESULTS:There was no difference regarding plasma levels of total cholesterol or low-density lipoprotein cholesterol between the two groups. The fractional clearance rate of triglycerides was 0.086 ± 0.044 in the obese group and 0.122 ± 0.026 in the controls (p = 0.040), and the fractional clearance rate of cholesterol ester (h−1) was 0.052 ± 0.021 in the obese subjects and 0.058 ± 0.015 (p = 0.971) in the controls.CONCLUSION:Grade III obese subjects exhibited normal low-density lipoprotein removal from plasma as tested by the nanoemulsion method, but triglyceride removal was slower.

In Vitro Assessment of the Bioaccessibility of Tocopherol and Fatty Acids from Sunflower Seed Oil Bodies

The in vitro digestibility (proteolytic and lipolytic) and bioaccessibility of nutritionally important compounds (alpha-tocopherol and fatty acids) have been studied for natural sunflower ( Helianthus annuus ) oil body suspensions in comparison to artificial emulsions emulsified with polyoxyethylene-20-sorbitan-monolaurate (Tween 20) or whey protein isolate. Proteolytic digestion of emulsions with pepsin (pH 2) promoted significant increases in mean particle size of the whey protein isolate stabilized emulsion (1.8-2.9 mum) and oil bodies (2.3-22.5 mum) but not the Tween 20 stabilized emulsions. SDS-PAGE of proteolytic digestion products suggested degradation of the stabilizing oleosin protein (ca. 18-21 kDa) in oil bodies. The rate of oil body hydrolysis with lipase was significantly slower than the lipase-catalyzed hydrolysis of the artificial emulsions and exhibited a prolonged lag phase. Results from simulated human digestion in vitro suggested that the mean bioaccessibility of alpha-tocopherol and total fatty acids from oil bodies (0.6 and 8.4%, respectively) was significantly lower than that from the Tween 20 stabilized emulsion (35 and 52%, respectively) and the whey protein isolate stabilized emulsion (17 and 33%, respectively). These in vitro results suggest that oil bodies could provide a natural emulsion in food that is digested at a relatively slow rate, the physiological consequence of which may be increased satiety.

The role of molecular physicochemical properties and apolipoproteins in association of drugs with triglyceride-rich lipoproteins: in-silico prediction of uptake by chylomicrons

The uptake of drugs by chylomicrons is a key element in both intestinal lymphatic transport and postprandial alterations in the disposition profile of lipophilic drugs. The aim of this article was to elucidate the factors that affect this phenomenon. The degree of association of 22 model lipophilic molecules with rat chylomicrons was assessed and correlated in silico with calculated physicochemical properties. The in-silico model was then validated using an external set of molecules. The uptake by chylomicrons was also compared to the association with a marketed artificial emulsion. The most important physicochemical property that affects the affinity to chylomicrons was found to be LogD7.4; however, a multiparameter model was required to describe properly the uptake process. The in-silico model (R2Y=0.91, R2X=0.91 and Q2=0.82) that was created using a combination of eight molecular descriptors enabled successful prediction of the affinity of the external set of molecules to chylomicrons. The association with the artificial emulsion was statistically different from the uptake by chylomicrons for four (out of nine) molecules. The association of drugs with chylomicrons is a complex process, which involves the lipophilic core as well as surface apoproteins. The in-silico model based on multiple physicochemical properties of the drugs is able to predict successfully the degree of association with chylomicrons.

The role of molecular physicochemical properties and apolipoproteins in association of drugs with triglyceride-rich lipoproteins: in-silico prediction of uptake by chylomicrons

Abstract Objectives The uptake of drugs by chylomicrons is a key element in both intestinal lymphatic transport and postprandial alterations in the disposition profile of lipophilic drugs. The aim of this article was to elucidate the factors that affect this phenomenon. Methods The degree of association of 22 model lipophilic molecules with rat chylomicrons was assessed and correlated in silico with calculated physicochemical properties. The in-silico model was then validated using an external set of molecules. The uptake by chylomicrons was also compared to the association with a marketed artificial emulsion. Key findings The most important physicochemical property that affects the affinity to chylomicrons was found to be LogD7.4; however, a multiparameter model was required to describe properly the uptake process. The in-silico model (R2Y = 0.91, R2X = 0.91 and Q2 = 0.82) that was created using a combination of eight molecular descriptors enabled successful prediction of the affinity of the external set of molecules to chylomicrons. The association with the artificial emulsion was statistically different from the uptake by chylomicrons for four (out of nine) molecules. Conclusions The association of drugs with chylomicrons is a complex process, which involves the lipophilic core as well as surface apoproteins. The in-silico model based on multiple physicochemical properties of the drugs is able to predict successfully the degree of association with chylomicrons.

High resting triacylglycerol turnover of rainbow trout exceeds the energy requirements of endurance swimming

Fish may use lipoproteins instead of albumin-bound fatty acids to fuel endurance exercise, but lipoprotein kinetics have never been measured in ectotherms. In vivo bolus injections of labeled very-low-density lipoproteins ((3)H-VLDL labeled in vivo from donor fish) and continuous infusions of Intralipid (3H-labeled artificial emulsion) were used to investigate the effects of prolonged exercise (6 h at 1.5 body length/s) and heparin (600 U/kg) on the turnover rate of circulating triacylglycerol (TAG) in rainbow trout. We hypothesized that swimming would stimulate TAG turnover rate to fuel working muscles and that heparin would reduce flux by releasing lipoprotein lipase (LPL) from endothelial cells. Results from both tracer methods show that the baseline TAG turnover rate of trout ranges from 24 to 49 mumol TAG.kg(-1) x min(-1) and exceeds all values measured to date in endotherms. More important, this high resting turnover rate is not stimulated during swimming, because it can already cover several times the energy requirements of locomotion. The fact that heparin causes a 50% decrease in baseline TAG turnover rate suggests that fish LPL must be bound to the endothelium for normal tissue uptake of fatty acids supplied by lipoproteins, as in mammals. We propose that the high resting TAG turnover rate of rainbow trout could be needed by ectotherms for rapid restructuring of membrane phospholipids. The continuous tracer infusion method implemented here could be a versatile tool to investigate the potential role of lipoproteins in providing fatty acids for rapid homeoviscous adaptation.

Association of adiponectin plasma levels with lipoprotein lipase activity in diabetes and coronary artery disease

In plasma, adiponectin is the most abundant adipocyte-specific protein. Low levels of adiponectin have been shown to be associated with obesity, type 2 diabetes, dyslipidemia and coronary artery disease (CAD), but the underlying mechanisms are incompletely understood. We speculated that the influence of adiponectin on the lipid profile and CAD risk could, in part, be mediated by lipoprotein lipase (LPL), because like adiponectin, LPL is secreted from adipose tissue, and low LPL is related to dyslipidemia and CAD. To test this hypothesis, we quantitated adiponectin levels in plasma by ELISA and used an artificial emulsion and an ELISA to measure LPL activity and concentration in the post heparin plasma of 245 patients undergoing elective coronary angiography. In our patients, low adiponectin was associated with low HDL cholesterol (p<0.001), elevated plasma triglycerides (p<0.001) and VLDL cholesterol (p<0.001), and the extent of CAD (number of diseased vessels, p=0.002 and CAD extent score, p=0.003). In multivariate analysis including age, BMI, insulin levels and polymorphisms in the LPL gene, adiponectin was the factor with the greatest influence on LPL activity (p=0.002) and concentration (p<0.01). For quartiles of increasing adiponectin levels, there was a continuous increase of LPL activity (144±57, 170±69, 175±73, 192±64 nmol/ml/min, p=0.003) and concentration (237±90, 291±100, 302±112, 348±153 ng/ml, p<0.001). Additionally, low adiponectin was associated with lower LPL concentration (r=0.353, P<0.001) and LPL activity (r=0.315, P=0.001) in a cohort of 108 type 2 diabetic patients. These data show that in both, patients with CAD and type 2 diabetics, adiponectin is strongly associated with LPL levels in vivo, and that at least part of the effect of adiponectin on lipid profile and CAD risk may be mediated by LPL.

Exercise training effects on the process of esterification and plasma removal of cholesterol of an artificial lipidic emulsion similar to LDL

Exercise training effects on the process of esterification and plasma removal of cholesterol of an artificial lipidic emulsion similar to LDL

Acute in vivo chylomicron metabolism and postalimentary lipoprotein alterations in normolipidemic male smokers

Increased postprandial lipemia has been stated as one of the mechanisms responsible for atherogenesis in smokers. We measured the postalimentary lipid response and the in vivo intravascular delipidation index of an artificial chylomicron emulsion in healthy adult smokers and controls. The blood was collected in the fasting state immediately after the smokers smoked one cigarette. The lipemia was measured 2, 4, 6 and 8 h postalimentarily in smokers (S, n=8) and in non-smoking controls (C, n=8) and the chylomicron metabolism rate was measured 2, 4, 6, 8, 12, 16, 20, 24 and 30 min after the injection of an artificial emulsion to S ( n=10) and to C ( n=10). The lipoproteins were isolated in the fasting period and 4 h after the fatty meal and their chemical composition in cholesterol, triglycerides, phospholipids and protein was determined. Smokers showed an increased lipolysis percentage value (mean±S.E.M.) of the artificial chylomicron (39.1±3.1) compared to controls (26.5±3.3) and higher levels of HDL 2-PL: 28.4±4.3 (S) versus 16.2±2.0 (C) mg/dl (mean±S.E.M.). In conclusion, the oral fat tolerance was not altered in smokers but an upregulation of the rate of metabolism of the TG-rich lipoproteins was elicited immediately after smoking one cigarette.

Plasma kinetics of an artificial emulsion resembling chylomicrons in patients with chronic lymphocytic leukemia.

Chylomicrons are the lipoproteins that transport dietary lipids in the blood. Although neoplastic diseases are often accompanied by alterations in lipid metabolism, chylomicrons are scarcely explored in cancer, despite their importance for the body's energy supply. Moreover, no data are available regarding chylomicron metabolism in chronic lymphocytic leukemia (CLL). Chylomicron metabolism in the bloodstream consists of lipolysis by lipoprotein lipase and uptake of remnants by the liver and is difficult to assess in the human body. Among the methods to evaluate this pathway, the determination of the plasma kinetics of triglyceride-rich emulsions that mimic chylomicrons is a practical and straightforward approach. A double-labeled chylomicron-resembling emulsion was injected into 10 patients with CLL and into 11 normolipidemic healthy subjects. The plasma kinetic curves of the emulsion 3H-triglyceride and 14Ccholesteryl ester were determined in plasma samples collected over 30 min. The fractional clearance rate (FCR) of triglycerides in CLL was not changed compared with controls. The FCR of cholesteryl esters was also no different from controls. These results indicate that chylomicron lipolysis and remnant removal are not affected in CLL.

Uptake of triacylglycerol-rich artificial emulsion particles by macrophage is a clathrin and apo-E lipoprotein-dependent process

Uptake of triacylglycerol-rich artificial emulsion particles by macrophage is a clathrin and apo-E lipoprotein-dependent process