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55-400: There is an inverse relationship in the density and size of lipoprotein particles: fats have a lower density than water or smaller protein molecules, and the larger particles have a higher ratio of internal fat molecules with respect to the outer emulsifying protein molecules in the shell. ULDLs, if in the region of 1,000 nm or more, are the only lipoprotein particles that can be seen using

110-728: A suspension , can be studied in terms of zeta potential , which indicates the repulsion between droplets or particles. If the size and dispersion of droplets does not change over time, it is said to be stable. For example, oil-in-water emulsions containing mono- and diglycerides and milk protein as surfactant showed that stable oil droplet size over 28 days storage at 25 °C. The stability of emulsions can be characterized using techniques such as light scattering, focused beam reflectance measurement, centrifugation, and rheology . Each method has advantages and disadvantages. The kinetic process of destabilization can be rather long – up to several months, or even years for some products. Often

165-447: A "water-in-oil" emulsion or an "oil-in-water" emulsion depends on the volume fraction of both phases and the type of emulsifier (surfactant) (see Emulsifier , below) present. Emulsion stability refers to the ability of an emulsion to resist change in its properties over time. There are four types of instability in emulsions: flocculation , coalescence , creaming / sedimentation , and Ostwald ripening . Flocculation occurs when there

220-674: A chylomicron remnant. ApoB48 and APOE are important to identify the chylomicron remnant in the liver for endocytosis and breakdown. Hyperchylomicronemia is characterized by an excessive presence of chylomicrons in the blood, leading to extreme hypertriglyceridemia . Clinical manifestations of this disorder include eruptive xanthomas , lipaemia retinalis , hepatosplenomegaly , recurrent abdominal pain , and acute pancreatitis . This condition can be caused by genetic mutations (see below) or secondary factors such as uncontrolled diabetes or alcohol use disorder . Hypochylomicronemia refers to abnormally low levels or complete absence of chylomicrons in

275-440: A dispersed and a continuous phase, with the boundary between the phases called the "interface". Emulsions tend to have a cloudy appearance because the many phase interfaces scatter light as it passes through the emulsion. Emulsions appear white when all light is scattered equally. If the emulsion is dilute enough, higher-frequency (shorter-wavelength) light will be scattered more, and the emulsion will appear bluer  – this

330-485: A light microscope, at maximum magnification. All the other classes are submicroscopic. Chylomicrons transport lipids absorbed from the intestine to adipose , cardiac, and skeletal muscle tissue, where their triglyceride components are hydrolyzed by the activity of the lipoprotein lipase , allowing the released free fatty acids to be absorbed by the tissues. When a large portion of the triglyceride core has been hydrolyzed, chylomicron remnants are formed and are taken up by

385-407: A liquid. Note 1 : The definition is based on the definition in ref. Note 2 : The droplets may be amorphous, liquid-crystalline, or any mixture thereof. Note 3 : The diameters of the droplets constituting the dispersed phase usually range from approximately 10 nm to 100 μm; i.e., the droplets may exceed the usual size limits for colloidal particles. Note 4 : An emulsion

440-411: A mixture of surfactants , co-surfactants, and co- solvents . The required surfactant concentration in a microemulsion is, however, several times higher than that in a translucent nanoemulsion, and significantly exceeds the concentration of the dispersed phase. Because of many undesirable side-effects caused by surfactants, their presence is disadvantageous or prohibitive in many applications. In addition,

495-417: A number of process advantages, including prevention of coagulation of product. Products produced by such polymerisations may be used as the emulsions – products including primary components for glues and paints. Synthetic latexes (rubbers) are also produced by this process. Hypertriglyceridemia Hypertriglyceridemia is the presence of high amounts of triglycerides in the blood . Triglycerides are

550-695: A sound scientific basis. An emulsifier is a substance that stabilizes an emulsion by reducing the oil-water interface tension . Emulsifiers are a part of a broader group of compounds known as surfactants , or "surface-active agents". Surfactants are compounds that are typically amphiphilic , meaning they have a polar or hydrophilic (i.e., water-soluble) part and a non-polar (i.e., hydrophobic or lipophilic ) part. Emulsifiers that are more soluble in water (and, conversely, less soluble in oil) will generally form oil-in-water emulsions, while emulsifiers that are more soluble in oil will form water-in-oil emulsions. Examples of food emulsifiers are: In food emulsions,

605-454: Is a hereditary predisposition to both primary and secondary hypertriglyceridemia. Acute pancreatitis may occur in people whose triglyceride levels are above 1000 mg/dL (11.3 mmol/L). Hypertriglyceridemia is associated with 1–4% of all cases of pancreatitis. The symptoms are similar to pancreatitis secondary to other causes, although the presence of xanthomas or risk factors for hypertriglyceridemia may offer clues. The diagnosis

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660-443: Is a hereditary predisposition to both primary and secondary hypertriglyceridemia. The National Cholesterol Education Program has set guidelines for triglyceride levels: These levels are tested after fasting 8 to 12 hours. Triglyceride levels remain temporarily higher for a period after eating. The AHA recommends an optimal triglyceride level of 100   mg/dL (1.1   mmol/L) or lower to improve heart health. In 2016,

715-777: Is a rare autosomal recessive disorder caused by mutations in both alleles of the MTP gene . This genetic defect leads to nearly undetectable levels of ApoB and very low plasma cholesterol levels. Patients with ABL exhibit fat malabsorption, steatorrhea , and fat accumulation in enterocytes and hepatocytes. The condition also results in multiple vitamin deficiencies (E, A, K, and D) due to impaired lipoprotein assembly and transport. If untreated, ABL can cause neurological disturbances such as spinal-cerebellar degeneration, peripheral neuropathies , and retinitis pigmentosa . Early supplementation of fat-soluble vitamins can prevent these complications. Homozygous hypobetalipoproteinemia (Ho-HBL; OMIM 107730)

770-632: Is a rare autosomal recessive disorder caused by mutations in the SAR1B gene . Patients with CMRD present with chronic diarrhea, failure to thrive, hypocholesterolemia, and low levels of fat-soluble vitamins. The enterocytes of these patients fail to secrete chylomicrons into the lymph, leading to lipid accumulation and characteristic mucosal changes in the small intestine. Unlike ABL and Ho-HBL, CMRD does not cause acanthocytosis, retinitis pigmentosa, or severe neurological symptoms. Familial chylomicronemia syndrome (FCS), also known as Type I hyperlipoproteinemia ,

825-531: Is achieved by applying an aqueous surfactant solution to the fuel through a high-pressure nozzle. Emulsifiers are not effective at extinguishing large fires involving bulk/deep liquid fuels, because the amount of emulsifier agent needed for extinguishment is a function of the volume of the fuel, whereas other agents such as aqueous film-forming foam need cover only the surface of the fuel to achieve vapor mitigation. Emulsions are used to manufacture polymer dispersions – polymer production in an emulsion 'phase' has

880-402: Is an attractive force between the droplets, so they form flocs, like bunches of grapes. This process can be desired, if controlled in its extent, to tune physical properties of emulsions such as their flow behaviour. Coalescence occurs when droplets bump into each other and combine to form a larger droplet, so the average droplet size increases over time. Emulsions can also undergo creaming, where

935-610: Is an extremely rare inherited disorder characterized by improper packaging and secretion of apoB-containing lipoproteins due to mutations in both alleles of the APOB gene . These mutations lead to apoB truncations or amino acid substitutions, resulting in the formation of short, abnormal apoBs that are unable to bind lipids and form chylomicrons. Clinical manifestations vary, ranging from lack of symptoms to features overlapping with those of ABL, including fat malabsorption and vitamin deficiencies. Chylomicron retention disease (CMRD; OMIM #607689)

990-544: Is called the " Tyndall effect ". If the emulsion is concentrated enough, the color will be distorted toward comparatively longer wavelengths, and will appear more yellow . This phenomenon is easily observable when comparing skimmed milk , which contains little fat, to cream , which contains a much higher concentration of milk fat. One example would be a mixture of water and oil. Two special classes of emulsions – microemulsions and nanoemulsions, with droplet sizes below 100 nm – appear translucent. This property

1045-454: Is characterized by massive hypertriglyceridemia , abdominal pain, pancreatitis, eruptive xanthomas , and hepatosplenomegaly . This condition is caused by mutations in genes such as LPL, APOC-II, APOA-V, LMF1, and GPIHBP1, which are involved in the regulation of triglyceride-rich lipoprotein catabolism. Patients with FCS show significantly elevated fasting concentrations of chylomicrons and do not typically develop premature atherosclerosis due to

1100-746: Is continuous depends in many cases on the pharmaceutical formulation . These emulsions may be called creams , ointments , liniments (balms), pastes , films , or liquids , depending mostly on their oil-to-water ratios, other additives, and their intended route of administration . The first 5 are topical dosage forms , and may be used on the surface of the skin , transdermally , ophthalmically , rectally , or vaginally . A highly liquid emulsion may also be used orally , or may be injected in some cases. Microemulsions are used to deliver vaccines and kill microbes . Typical emulsions used in these techniques are nanoemulsions of soybean oil , with particles that are 400–600 nm in diameter. The process

1155-664: Is due to the fact that light waves are scattered by the droplets only if their sizes exceed about one-quarter of the wavelength of the incident light. Since the visible spectrum of light is composed of wavelengths between 390 and 750 nanometers (nm), if the droplet sizes in the emulsion are below about 100 nm, the light can penetrate through the emulsion without being scattered. Due to their similarity in appearance, translucent nanoemulsions and microemulsions are frequently confused. Unlike translucent nanoemulsions, which require specialized equipment to be produced, microemulsions are spontaneously formed by "solubilizing" oil molecules with

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1210-420: Is exploited in soap , to remove grease for the purpose of cleaning . Many different emulsifiers are used in pharmacy to prepare emulsions such as creams and lotions . Common examples include emulsifying wax , polysorbate 20 , and ceteareth 20 . Sometimes the inner phase itself can act as an emulsifier, and the result is a nanoemulsion, where the inner state disperses into " nano-size " droplets within

1265-425: Is for the disinfection of surfaces. Some types of nanoemulsions have been shown to effectively destroy HIV-1 and tuberculosis pathogens on non- porous surfaces. Emulsifying agents are effective at extinguishing fires on small, thin-layer spills of flammable liquids ( class B fires ). Such agents encapsulate the fuel in a fuel-water emulsion, thereby trapping the flammable vapors in the water phase. This emulsion

1320-410: Is made on blood tests , often performed as part of screening . The normal triglyceride level is less than 150 mg/dL (1.7 mmol/L). Once diagnosed, other blood tests are usually required to determine whether the raised triglyceride level is caused by other underlying disorders ("secondary hypertriglyceridemia") or whether no such underlying cause exists ("primary hypertriglyceridaemia"). There

1375-411: Is not chemical, as with other types of antimicrobial treatments, but mechanical. The smaller the droplet the greater the surface tension and thus the greater the force required to merge with other lipids . The oil is emulsified with detergents using a high-shear mixer to stabilize the emulsion so, when they encounter the lipids in the cell membrane or envelope of bacteria or viruses , they force

1430-484: Is referred to as chyle . The lymphatic circulation carries chyle to the lymphatic ducts before it enters the venous return of the systemic circulation via subclavian veins . From here, chylomicrons can supply tissue throughout the body with fat absorbed from the diet. Because they enter the bloodstream in this way, digested lipids (in the form of chylomicrons) bypass the hepatic portal system and thus avoid first pass metabolism , unlike digested carbohydrates (in

1485-457: Is required. Medications are recommended in those with high levels of triglycerides that are not corrected with lifestyle modifications, with fibrates being recommended first. Epanova (omega-3-carboxylic acids) is another prescription drug used to treat very high levels of blood triglycerides. As of 2006, the prevalence of hypertriglyceridemia in the United States was 30%. Analysis of

1540-434: Is termed an oil/water (o/w) emulsion if the dispersed phase is an organic material and the continuous phase is water or an aqueous solution and is termed water/oil (w/o) if the dispersed phase is water or an aqueous solution and the continuous phase is an organic liquid (an "oil"). Note 5 : A w/o emulsion is sometimes called an inverse emulsion. The term "inverse emulsion" is misleading, suggesting incorrectly that

1595-652: The United States Preventive Services Task Force concluded that testing the general population under the age of 40 without symptoms is of unclear benefit. Lifestyle changes including weight loss, exercise and dietary modification may improve hypertriglyceridemia. This may include dietary changes such as restriction of fat and carbohydrates (specifically fructose and sugar-sweetened beverages ) and increased consumption of omega-3 fatty acids from algae, nuts, and seeds. The decision to treat hypertriglyceridemia with medication depends on

1650-399: The liver and spleen ), and neurological symptoms. Some experience attacks of abdominal pain that may be mild episodes of pancreatitis. Eruptive xanthomas are 2–5 mm papules, often with a red ring around them, that occur in clusters on the skin of the trunk, buttocks and extremities. Familial dysbetalipoproteinemia causes larger, tuberous xanthomas; these are red or orange and occur on

1705-426: The tunica intima and become trapped in the subendothelial space. This process enhances the deposition of cholesterol in the arterial wall, which is a critical step in the formation of atherosclerotic plaques . The retention and modification of these remnants within the arterial wall trigger inflammatory responses , further accelerating the development of atherosclerosis . Abetalipoproteinemia (ABL; OMIM 200100)

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1760-538: The ER membrane. During transit through the Golgi, nascent chylomicrons undergo enzymatic modification and lipidation processes, resulting in the formation of mature chylomicrons . Mature chylomicrons are released through the basolateral membrane of enterocytes (via the secretory pathway ) into lacteals , lymphatic capillaries in the villi of the small intestine . Lymph that contains chylomicrons (and other emulsified fats)

1815-530: The blood, particularly after a meal (postprandial). This condition can result from genetic mutations (see below), as well as certain malabsorption syndromes or deficiencies in dietary fat intake. Chylomicron remnants are the lipoprotein particles left after chylomicrons have delivered triglycerides to tissues. Elevated levels of these remnants contribute to hyperlipidemia , which is considered an important risk factor for cardiovascular disease . Recent studies have demonstrated that chylomicron remnants can penetrate

1870-501: The case of non-ionic surfactants or, on a broader scope, interactions between droplets within the system. Storing an emulsion at high temperatures enables the simulation of realistic conditions for a product (e.g., a tube of sunscreen emulsion in a car in the summer heat), but also accelerates destabilization processes up to 200 times. Mechanical methods of acceleration, including vibration, centrifugation, and agitation, can also be used. These methods are almost always empirical, without

1925-582: The continuous phase (sometimes referred to as the "dispersion medium") are usually assumed to be statistically distributed to produce roughly spherical droplets. The term "emulsion" is also used to refer to the photo-sensitive side of photographic film . Such a photographic emulsion consists of silver halide colloidal particles dispersed in a gelatin matrix. Nuclear emulsions are similar to photographic emulsions, except that they are used in particle physics to detect high-energy elementary particles . A fluid system in which liquid droplets are dispersed in

1980-416: The dispersed phase is denser than the continuous phase and the gravitational forces pull the denser globules towards the bottom of the emulsion. Similar to creaming, sedimentation follows Stokes' law . An appropriate surface active agent (or surfactant) can increase the kinetic stability of an emulsion so that the size of the droplets does not change significantly with time. The stability of an emulsion, like

2035-459: The droplets rise to the top of the emulsion under the influence of buoyancy , or under the influence of the centripetal force induced when a centrifuge is used. Creaming is a common phenomenon in dairy and non-dairy beverages (i.e. milk, coffee milk, almond milk , soy milk) and usually does not change the droplet size. Sedimentation is the opposite phenomenon of creaming and normally observed in water-in-oil emulsions. Sedimentation happens when

2090-409: The elbows and knees. Palmar crease xanthomas may also occur. The diagnosis is made on blood tests , often performed as part of screening . Once diagnosed, other blood tests are usually required to determine whether the raised triglyceride level is caused by other underlying disorders ("secondary hypertriglyceridemia") or whether no such underlying cause exists ("primary hypertriglyceridemia"). There

2145-457: The emulsion has properties that are the opposite of those of an emulsion. Its use is, therefore, not recommended. The word "emulsion" comes from the Latin emulgere "to milk out", from ex "out" + mulgere "to milk", as milk is an emulsion of fat and water, along with other components, including colloidal casein micelles (a type of secreted biomolecular condensate ). Emulsions contain both

2200-400: The emulsion. An example of this is seen in the separation of the oil and vinegar components of vinaigrette , an unstable emulsion that will quickly separate unless shaken almost continuously. There are important exceptions to this rule – microemulsions are thermodynamically stable, while translucent nanoemulsions are kinetically stable. Whether an emulsion of oil and water turns into

2255-562: The form of monosaccharides ) and proteins (in the form of amino acids ). While circulating in blood, high-density lipoproteins (HDLs) donate essential components including apolipoprotein C-II (APOC2) and apolipoprotein E (APOE) to the mature chylomicron. APOC2 is a crucial coenzyme for the activity of lipoprotein lipase (LPL), which hydrolyzes triglycerides within chylomicrons. Once triglyceride stores are distributed, chylomicrons return APOC2 to HDLs while retaining APOE, transforming into

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2310-399: The formulator must accelerate this process in order to test products in a reasonable time during product design. Thermal methods are the most commonly used – these consist of increasing the emulsion temperature to accelerate destabilization (if below critical temperatures for phase inversion or chemical degradation). Temperature affects not only the viscosity but also the interfacial tension in

2365-464: The large size of chylomicrons preventing their traversal through the vascular endothelial barrier. Diagnosis is confirmed by DNA sequencing for pathogenic mutations in these genes. Emulsifying An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation . Emulsions are part of a more general class of two-phase systems of matter called colloids . Although

2420-411: The levels and on the presence of other risk factors for cardiovascular disease. Very high levels that would increase the risk of pancreatitis is treated with a drug from the fibrate class. Niacin and omega-3 fatty acids as well as drugs from the statin class may be used in conjunction, with statins being the main drug treatment for moderate hypertriglyceridemia where reduction of cardiovascular risk

2475-516: The lipids to merge with themselves. On a mass scale, in effect this disintegrates the membrane and kills the pathogen. The soybean oil emulsion does not harm normal human cells, or the cells of most other higher organisms , with the exceptions of sperm cells and blood cells , which are vulnerable to nanoemulsions due to the peculiarities of their membrane structures. For this reason, these nanoemulsions are not currently used intravenously (IV). The most effective application of this type of nanoemulsion

2530-695: The liver, thereby also transferring dietary fat to the liver. In the small intestine, dietary triglycerides are emulsified by bile and digested by pancreatic lipases , resulting in the formation of monoglycerides and fatty acids . These lipids are absorbed into enterocytes via passive diffusion . Inside these cells, monoglycerides and fatty acids are transported to the smooth endoplasmic reticulum (smooth ER), where they are re-esterified to form triglycerides. These triglycerides, along with phospholipids and cholesterol, are added to apolipoprotein B 48 to form nascent chylomicrons (also referred to as immature chylomicrons or pre-chylomicrons ). After synthesis in

2585-661: The most abundant fatty molecule in most organisms. Hypertriglyceridemia occurs in various physiologic conditions and in various diseases, and high triglyceride levels are associated with atherosclerosis , even in the absence of hypercholesterolemia (high cholesterol levels) and predispose to cardiovascular disease . Chronically elevated serum triglyceride levels are a component of metabolic syndrome and metabolic dysfunction-associated steatotic liver disease , both of which typically involve obesity and contribute significantly to cardiovascular mortality in industrialised countries as of 2021. Extreme triglyceride levels also increase

2640-405: The oil is the dispersed phase, and water is the continuous phase. Second, they can form a water-in-oil emulsion, in which water is the dispersed phase and oil is the continuous phase. Multiple emulsions are also possible, including a "water-in-oil-in-water" emulsion and an "oil-in-water-in-oil" emulsion. Emulsions, being liquids, do not exhibit a static internal structure. The droplets dispersed in

2695-478: The outer phase. A well-known example of this phenomenon, the " ouzo effect ", happens when water is poured into a strong alcoholic anise -based beverage, such as ouzo , pastis , absinthe , arak , or raki . The anisolic compounds, which are soluble in ethanol , then form nano-size droplets and emulsify within the water. The resulting color of the drink is opaque and milky white. A number of different chemical and physical processes and mechanisms can be involved in

2750-485: The process of emulsification: Oil-in-water emulsions are common in food products: Water-in-oil emulsions are less common in food, but still exist: Other foods can be turned into products similar to emulsions, for example meat emulsion is a suspension of meat in liquid that is similar to true emulsions. In pharmaceutics , hairstyling , personal hygiene , and cosmetics , emulsions are frequently used. These are usually oil and water emulsions but dispersed, and which

2805-495: The risk of acute pancreatitis . Hypertriglyceridemia itself is usually symptomless, although high levels may be associated with skin lesions known as xanthomas . Most people with elevated triglycerides experience no symptoms. Some forms of primary hypertriglyceridemia can lead to specific symptoms: both familial chylomicronemia and primary mixed hyperlipidemia include skin symptoms (eruptive xanthoma ), eye abnormalities (lipemia retinalis), hepatosplenomegaly (enlargement of

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2860-515: The smooth ER, nascent chylomicrons are transported to the Golgi apparatus by SAR1B proteins. The transport of nascent chylomicrons within the secretory pathway is facilitated by protein transport vesicles (PCTVs). PCTVs are uniquely equipped with v-SNARE and VAMP-7 proteins, which aid in their fusion with the cis-Golgi compartment. This transport is facilitated by COPII proteins, including Sec23/24, which select cargo and facilitate vesicle budding from

2915-418: The stability of a microemulsion is often easily compromised by dilution, by heating, or by changing pH levels. Common emulsions are inherently unstable and, thus, do not tend to form spontaneously. Energy input – through shaking, stirring, homogenizing , or exposure to power ultrasound  – is needed to form an emulsion. Over time, emulsions tend to revert to the stable state of the phases comprising

2970-538: The terms colloid and emulsion are sometimes used interchangeably, emulsion should be used when both phases, dispersed and continuous, are liquids. In an emulsion, one liquid (the dispersed phase ) is dispersed in the other (the continuous phase). Examples of emulsions include vinaigrettes , homogenized milk , liquid biomolecular condensates , and some cutting fluids for metal working . Two liquids can form different types of emulsions. As an example, oil and water can form, first, an oil-in-water emulsion, in which

3025-443: The type of emulsifier greatly affects how emulsions are structured in the stomach and how accessible the oil is for gastric lipases , thereby influencing how fast emulsions are digested and trigger a satiety inducing hormone response. Detergents are another class of surfactant, and will interact physically with both oil and water , thus stabilizing the interface between the oil and water droplets in suspension. This principle

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