Coating of hollow needles

For the examination of body fluids, modern and largely automated medical diagnostics uses various metallic hollow needles in its analysis devices to pipette the samples and reagents.

These hollow needles are made of high-quality stainless steel and are of the highest quality inside and outside. However, the untreated steel surface is hydrophilic, i.e. liquids adhere to such surfaces. Despite intermediate cleaning, this can lead to undesirable and dangerous carry-over effects during analysis. This danger is eliminated by hydrophobizing and partially surface smoothing, very durable, innovative coatings.


We coat tubes and cannulas made of glass, stainless steel and plastic from an inside diameter of 0.1 mm and up to a length of 500 mm.

Internal and external coatings

The inner surfaces of hollow needles are coated with a hydrophobic and oleophobic sol-gel nanocomposite layer or PTFE. On the outside, all layer types can be applied, from sol-gel nanocomposites to fluoropolymers/PEEK to hard material layers.

The coated needles have the following properties, for example:

  • Easy-to-Clean: Easier cleaning and lower consumption of cleaning fluid
  • Non-carry-over: carry-overs (e.g. peptides) are greatly reduced
  • Non-stick properties
  • Better dosing and repeat accuracy
  • Extension of the service life of the product
  • Diffusion barrier against iron ions