Combining Solid Phase Microextraction and Derivatization for Analysis of THC and Metabolite in Surface Waters
Oral Presentation
Prepared by K. Stenerson
Sigma-Aldrich/Supelco, 595 Harrison Road, Bellefonte, PA, 16823, United States
Contact Information: [email protected]; 814-359-5781
ABSTRACT
Solid Phase microextraction (SPME) is a solvent-less extraction technique that was introduced in the early 1990’s. Since that time it has been used to extract and analyze a wide variety of matrices and analytes. In the environmental laboratory, its use has been primarily for the analysis of VOCs and some classes of semivolatiles. The compounds in these applications are amenable to GC analysis directly, i.e., chemical derivatization is not required to stabilize them for the GC process. In the case of compounds that cannot be analyzed directly by GC, such as those containing polar functional groups, derivatization is required prior to analysis. For environmental samples, this is done as an extra step after extraction and subsequent drying of the extract. In the case of SPME, after extraction, derivatization can be performed directly on the fiber. This can extend the usefulness of SPME to classes of compounds which do not normally perform well in a GC analysis. Examples of such compounds are drugs of abuse, many of which contain polar functional groups.
Cannabis is a schedule 1 substance under US federal law; however four states (Colorado, Washington, Alaska, and Oregon) have legalized it for recreational and medical use. The level of use by the general public is typically determined through questionnaires and crime statistics; however this may not give an accurate assessment. Sewage epidemiology seeks to correlate data from these surveys with actual levels found in wastewater. In the case of cannabis, this can be one by analyzing for the psychoactive substance, tetrahydrocannabinol (THC), and the major metabolite, carboxytetrahydrocannabinol (THCCOOH). This presentation will discuss the use of SPME with on-fiber derivatization as a simple, quick, and sensitive approach to analysis of THC and THCCOOH from treated effluent and surface water.
Oral Presentation
Prepared by K. Stenerson
Sigma-Aldrich/Supelco, 595 Harrison Road, Bellefonte, PA, 16823, United States
Contact Information: [email protected]; 814-359-5781
ABSTRACT
Solid Phase microextraction (SPME) is a solvent-less extraction technique that was introduced in the early 1990’s. Since that time it has been used to extract and analyze a wide variety of matrices and analytes. In the environmental laboratory, its use has been primarily for the analysis of VOCs and some classes of semivolatiles. The compounds in these applications are amenable to GC analysis directly, i.e., chemical derivatization is not required to stabilize them for the GC process. In the case of compounds that cannot be analyzed directly by GC, such as those containing polar functional groups, derivatization is required prior to analysis. For environmental samples, this is done as an extra step after extraction and subsequent drying of the extract. In the case of SPME, after extraction, derivatization can be performed directly on the fiber. This can extend the usefulness of SPME to classes of compounds which do not normally perform well in a GC analysis. Examples of such compounds are drugs of abuse, many of which contain polar functional groups.
Cannabis is a schedule 1 substance under US federal law; however four states (Colorado, Washington, Alaska, and Oregon) have legalized it for recreational and medical use. The level of use by the general public is typically determined through questionnaires and crime statistics; however this may not give an accurate assessment. Sewage epidemiology seeks to correlate data from these surveys with actual levels found in wastewater. In the case of cannabis, this can be one by analyzing for the psychoactive substance, tetrahydrocannabinol (THC), and the major metabolite, carboxytetrahydrocannabinol (THCCOOH). This presentation will discuss the use of SPME with on-fiber derivatization as a simple, quick, and sensitive approach to analysis of THC and THCCOOH from treated effluent and surface water.
