Nonderivatized Sarcosine Analysis by Gas Chromatography after Solid-Phase Microextraction by Newly Synthesized Monolithic Molecularly Imprinted Polymer

In this study, a simple method for analysis of nonderivatized sarcosine was developed by gas chromatography. It is based on solid-phase microextraction of sarcosine on a novel synthesized solid-phase microextraction (SPME) fiber. A monolithic SPME fiber was fabricated based on a molecularly imprinted polymer that could be coupled with gas chromatography for extraction and determination of sarcosine. Extraction time, pH, and ionic strength were investigated as important factors in the extraction procedure. The fabricated fiber was firm, inexpensive, stable, and selective, which are vital characteristics for SPME. The selectivity of the fabricated fiber in relation to analog compounds was also investigated. Under optimum conditions, the calibration curve was linear in the range of 1–100 mg L⁻¹ (R ² = 0.987). High extraction efficiency for sarcosine was obtained with a detection limit of 0.37 mg L⁻¹. The fabricated fiber was successfully applied for SPME of sarcosine from urine after its extraction, followed by gas chromatography flame ionization detector analysis.