Bioinert (U)HPLC columns for bio-separations and coordinating compounds

Several substances are able to interact with quite inert column hardware materials such as stainless steel or titanium. Even if the stationary phase used is not showing any coordinating abilities due to the absence of metal impurities, interaction with the metallic surfaces is possible. The absorption on metallic surfaces typically leads to peak tailing, loss of recovery and sample carry over. This behaviour can especially be seen when a new column is used without any conditioning before the actual analysis. Critical substances for such behaviour are selected proteins and peptides, nucleotides and oligonucleotides and metal-coordinating small molecules, e.g. organophosphates.

Dedicated bioinert and metal-free hardware

YMC offers a special hardware as an option for their YMC-Triart (U)HPLC column family. The so-called metal-free YMC-Triart columns are fully bioinert columns due to their PEEK lined stainless steel column body and the use of PEEK frits. The stationary phase and hence the samples are only in contact with PEEK once the inside the column. Due to the use of stainless steel as outer body, the same pressure limits as for standard columns can be maintained, 100 MPa/1,000 bar for UHPLC purposes and 45 MPa/450 bar for HPLC use.

Ideal combination of stationary phase and hardware

Due to its organic/inorganic hybrid silica base material, YMC-Triart stationary phases contain virtually no metal impurities. In combination with the bioinert metal-free column hardware and metal-free systems, YMC-Triart columns show excellent peak shapes for sensitive compounds, prevent carry over and are ideal for the use of highly sensitive LC/MS analyses.

Phase options

All YMC-Triart phases with 1.9 µm for UHPLC or 3 or 5 µm for HPLC are available in this metal-free hardware. While YMC-Triart C18 or C8 with a standard pore size of 120 Å are standards for small and large molecules, widepore YMC-Triart Bio C4 and C18 with a pore size of 300 Å are preferred choices for BioLC tasks. The very hydrophobic YMC-Triart C18 ExRS, the aromatic YMC-Triart Phenyl and PFP as well as the polar YMC-Pack Diol-HILIC, all dedicated mainly for small molecules, complete the YMC-Triart column family.

How to get optimum results

Even though the most interactions with metal can take place in the column itself, YMC-Triart metal-free columns are best combined with bioinert or optimised “non-metal” UHPLC/HPLC systems to obtain optimum results. Furthermore, due to the column design the columns have to be attached using either connectors without a ferrule or with a flexible ferrule, such as MarvelXACT™ UHPLC/HPLC connectors. They are available either as PEEK-lined stainless steel or as PEEKsil ones.