Popper's family of PSX inert coatings are applied to tubular steel products (needles, probes, dispensing/aspirtaing probes, non-coring-septum-penetration needles)manufactured by Popper and Sons
PSX-CH is useful where you want to reduce carryover, improve reproducibility, and reduce interaction between the fluid and the walls of the substrate.
It has extremely low non-specific protein-binding characteristics, as well as non-blood protein binding characteristics.
PSX-H is primarily a surface treatment to provide for hydrophobic qualities.
The ceramic interlayer in the PSX-CH provides for a more uniform binding surface, so the actual protein bonding charateristics and hydrophobic value is better in the PSX-CH than in the PSX-H.
PSX-D is used to provide protection form the qualities that mixtures of water and DMSO have on surfaces.
Adding DMSO to water makes for an interesting chemical property that has transient polarities and surface energies that far exceed either of the two materials by themselves.
The problem is, therefore, that these liquids tend to cling to the surfaces they come in contact with, as they have an overall effect of very low critical surface tensions.
The DMSO-surface is taylored to provide a surface that will resist corrosion by the materials in the solutions, as well as provide for very low critical surface energies to help keep the DMSO-water solutions from clinging to the treated surfaces.
PSX-D is a process whereby the native oxides, nitrides, carbides and surface contaminants are removed, a uniform CMOS (complementary metal-oxide semiconductor) material is applied in a uniform and comformal manner to the entire surface, and then that surface is modified to lower the critical surface energy to it's lowest possible level.
PSX-CL is the halogen resistant surface.
This surface system was created in response to customers requests for a surface that would resist salt solutions, acids, and especially halides such as clorine (ie, Clorox).
It is comprised of many layers of different materials, each applied conformally, each used to slow the migration of small atoms (such as chloride ions) to the surface of the substrate to head off corrosion.
In one test, 304 stainless samples were subjected to a solution of sodium hydroxide and 21% sodium hypochlorite at 80C.
The untreated sample showed visible corrosion in 13 seconds while the treated sample lasted 26 hours before visible corrosion.
All of the PSX surfaces are better suited for acidic rather than basic environments; however, if the application requires resistance to strong bases, Popper can make all of the PSX surfaces resistant to bases as well; it says it has surfaces that can resist pH environments from 1 to 14.
