text: An effective sample preparation protocol, usually involving either liquid-liquid extraction (LLE) or solid phase extraction (SPE) and frequently derivatisation can remove ion suppressing species from the sample matrix prior to analysis. These common approaches may also remove other interferences, such as isobaric species.
  Protein precipitation is another method that can be employed for small molecule analysis. Removal of all protein species from the sample matrix may be effective in some cases, although for many analytes, ion suppressing species are not of protein origin and so this technique is often used in conjunction with extraction and derivatisation.