Coating architecture

2D Nano coating

For example, the wettability of a hydrophilic material like glass can be completely inverted by the formation of a hydrophobic 2D nanocoating, resulting in a surface with a water contact angle of over 110°.

Because of their directional binding to the surface, 2D nanocoatings possess a high degree of molecular order. This is beneficial for applications where detailed control of the functional groups present at the surface is of importance.

On the molecular level, Surfix’s 2D nanocoatings resemble a long pile carpet, with every strand corresponding to a single molecule. The thickness of the coating is determined by the length of the coating molecule, and is therefore limited to a few nanometers. Despite their extremely low thickness, 2D nanocoatings can drastically change the surface properties of a material.

3D Nano Coating

For some applications, a thicker nanocoating is preferred. This can be achieved by using a different nanocoating precursor, allowing the nanocoating to grow from the surface during the coating process. The result is a branched polymer film (3D nanocoating) with a thickness up to 100 nanometer.

When comparing the 2D and 3D hydrophobic nanocoatings, the increased thickness and microstructure of the 3D architecture result in an even more hydrophobic surface, with a water contact angle exceeding 130°.

3D nanocoatings are also beneficial for the immobilization of bioreceptors (e.g. antibodies, aptamers or DNA) on a biosensor. Owing to their higher thickness, 3D nanocoatings have a higher immobilization capacity compared to 2D nanocoatings, which improves the sensitivity and limit of detection of the biosensor.