Custom Premix Selecting "Custom Premix" option means that all of the beads you have chosen will be premixed in manufacturing before the kit is sent to you.
Purospher® STAR RP-18 endcapped is the best choice for HPLC separation of basic, neutral, metal chelating samples or indeed any other format. Its outstanding performance and stability, allows a maximum flexibility in method development. Robust methods can be developed across the entire pH spectrum from 1.5 to 10.5 enabling the use of the complete range of mobile phases.