Ontwsep™ Silica SPE CartridgesOntwsep Silica is an extraction cartridge that uses unbonded, high purity spherical silica gel as an adsorbent. It is slightly acidic and has a strong polar interaction. It is used to separate non polar or weakly polar chemicals, oils, and other substances, particularly those with identical structures. It may adsorb nonpolar and weakly polar substances, as well as oils. It also exhibits high selectivity for non polar weakly polar fat soluble molecules