Micelles

Micelles are a type of colloidal particle that are small enough to be suspended in liquid. They have no definite shape and take on the shape of the liquid they’re in, meaning they can’t be seen with the naked eye. One important property of micelles is that they repel each other, so when one is inside another, it’s as if there is no other particle present. Micelles have also been used to solve drug delivery problems because when one molecule is surrounded by many others, molecules within the micelles stick together more strongly than molecules outside them. Micelles are on the surface of your skin and they help keep it moisturised. They also trap bacteria and help prevent infections. 

What are Micelles?

Micelles are the tiny oil droplets that surround your skin. They are formed in your skin by the disruption of an oil-like lipid phase. Micelles can be created from contractile lipids in cell membranes or from lipids released into the aqueous phase of cells. Micelles are actually “macromolecular nanoparticles.” They measure about 200 nm to 300 nm (one micrometre) in diameter and contain 60 to 90 molecules of water and 20 to 30 molecules of oil. These molecules are formed with a hydrophobic core surrounded by a layer of water which acts like a protective shell.

Causes of Micelles:

Cholesterol is one of the main components that form micelles. Many chemicals, including steroids, cholesterol and others, can cause micelles to be formed. In fact, high levels of cholesterol can cause a dramatic increase in the formation of micelles. When high levels of cholesterol are found in the body, cells begin producing significantly more micelles as a result. If a body is made up mainly of cholesterol and triglycerides (both known for causing accumulation inside cells), the number of free oil molecules would be very low which could lead to the formation of large amounts of micelles within tissue.

Micelles and Ageing:

Another interesting fact about micelles is that their quantity decreases with ageing. As we age, more water evaporates from our skin which means that the amount of oil increases. With the increase in oil, micelles are formed. However, since there’s a loss of water within our bodies as we age, micelles are actually formed at a slower rate. Micelles may also change structure and function with age as well. Some studies have suggested that the skin of older people is less able to protect itself from damage by ultraviolet radiation because of changes in the way that cells form micelles. 

Antibacterial Properties of Micelles:

Micelles are highly effective in killing bacteria due to their antimicrobial properties. These antibacterial properties can be attributed to their repulsion effect created by hydrophobic interactions between the oil and water molecules within the micelles. These interactions reduce the total surface area available for bacterial adhesion, proliferation, and biofilm formation, thus decreasing the number of viable bacteria in the vicinity.

Micelles in Cell Membranes?

Micelles have been found to be important cellular structures. They’ve been discovered to be formed in the cell membrane and they can reversibly fuse with cells. However, it’s not exactly clear how or why they’re formed in a cell membrane. Micelles have also been found in many biological fluids such as blood, milk and lung surfactant. 

Micelles vs. Nanoparticles

Another popular colloidal particle is nanoparticles. Although both nanoparticles and micelles are tiny, micelles are actually much larger than nanoparticles (on the scale of hundreds of nanometers, while micelles are on the scale of dozens). Micelles also don’t have a precise shape like nanoparticles do. Micelles are composed of many smaller particles whereas nanoparticles are composed of one single large particle. Nanoparticles and micelles also differ in function. Nanoparticles tend to be harmful, while micelles are beneficial to the body.

Relation between Micelles and Microemulsions:

A microemulsion is a structure related to a micellar structure, but they’re actually quite different. A microemulsion is actually made up of water, oil, and surfactants rather than water, oil and lipids (or contractile lipids). They’re actually very different from micellar structures as well.

Where do we get Micelles?

Micelles are produced by high concentrations of lipids, such as triglycerides and phospholipids. It’s more likely that they’re produced when there is high traffic of lipids between cells. In this case, the extra lipids are responsible for causing micelles to form, leading to an increase in the amount of micelles in the environment. Micelles can also be formed in order to protect against inflammation. Inflammation is caused when structures in our bodies begin to swell or stretch out due to injury or over activation of various inflammatory pathways.

Conclusion:

Micelles are a very interesting colloidal system, which perform multiple useful functions. They’re important in the appearance of our skin and they also help to prevent infection on our skin. They make up a large portion of the oil present in our bodies and their volume can increase significantly with age. Micelles also play an important role in the way that our cells function as well, where they’re important for preventing damage to cells by free radicals and other harmful molecules.