Abstract: Polymeric adsorbents useful for solid phase extraction (SPE) comprising a copolymer formed by copolymerizing at least one hydrophobic monomer including divinylbenzene and at least one hydrophilic monomer including acrylonitrile are provided. Also provided are SPE cartridges including a divinylbenzene-acrylonitrile hydrophilic-lipophilic balance adsorbent. Further provided are methods of using a divinylbenzene-acrylonitrile hydrophilic-lipophilic balance adsorbent in conventional and simplified SPE techniques.

Abstract: Methods of assessing an analyte in a blood sample are provided according to aspects of the present disclosure which include: extracting the analyte from a biological sample dried on a treated support, producing an extracted sample, the treated support comprising a protein denaturant, wherein the analyte is a substrate for an enzyme present, or suspected of being present, in the biological sample, wherein the protein denaturant inhibits enzymatic activity of the enzyme on the analyte; and subjecting the extracted sample to liquid chromatography tandem mass spectrometry (LC/MS/MS), thereby assessing the analyte in the biological sample.

Abstract: Polymeric adsorbents useful for solid phase extraction (SPE) comprising a copolymer formed by copolymerizing at least one hydrophobic monomer including divinylbenzene and at least one hydrophilic monomer including acrylonitrile. Also provided are SPE cartridges including a divinylbenzene-acrylonitrile hydrophilic-lipophilic balance adsorbent. Further provides are methods of using a divinylbenzene-acrylonitrile hydrophilic-lipophilic balance adsorbent in conventional and simplified SPE techniques.