Polymeric sorbents are comprised from organic polymers which are then functionalized with specific ligands to give retention of analyte molecules. Therefore, there is no silica support and no surface silanol groups which can contribute to unwanted secondary interactions. Polymeric sorbents have a much higher surface area; hence, they have a higher loading capacity compared to traditional silica-based sorbents. Silica is inherently unstable at extremes of pH. Polymeric sorbents, however, have a much larger pH stability range (pH 0-14) allowing them to be used for applications that require these extreme separation conditions. A variety of chemistries have been developed in order to separate various analyte types.