Surfactants (short for “surface active agents”) are organic chemicals that change the interaction between water, soils and surfaces.
They’re able to do so because they contain both hydrophilic and hydrophobic groups. In a surfactant, the hydrophilic side of the molecule attaches to water, and the hydrophobic side of the molecule avoids it. By lowering the surface tension of water, surfactants enable a detergent to wet a surface more quickly, so soil can be readily loosened and removed.
What is surface tension?
If you’ve ever seen drops of water form beads on a hard surface, you’re watching water molecules do what they do best: stick together. This surface tension causes water molecules to cling to other water molecules and reject other objects (the same reason you can float a needle on water).
How do surfactants work?
Surfactants help to reduce this surface tension because, while the hydrophilic head holds tight to the water molecules, the hydrophobic tail attaches to oils and hard surfaces. This spreads the water more evenly across the surface, and joins waters and soils together so that the soils can be lifted from surfaces.
Let’s imagine that we’re washing a heavily-soiled lab cage and see how the surfactants work:
During washing, the surfactant mixes with water.
The soil-loving ends of the surfactant molecules attach themselves to the organic proteins on the surfaces. The scrubbing and agitation breaks the soils into smaller, easier-to-remove pieces.
During wiping and rinsing, water molecules moving past attach themselves to the opposite, water-loving ends of the surfactant molecules, allowing the soils to be pulled from the surface.
As you can see, surfactants play a major role in the lifting of stains and soils, and can reduce employee strain when dealing with tough soils such as those found in animal-housing facilities and food processing plants. Looking for more? You can find surfactants in a variety of Quip Laboratories products, including our AqueLyn 9 PLUS II cleaner.