Microwave-modified pencil lead molecularly imprinted polymer coating as SPME fiber for ketoprofen bioanalysis and pharmacokinetic study; A rapid and mass-produced microwave-assisted polymerization.

BACKGROUND

In recent decades, introducing new fibers has improved the SPME method. Commercial fibers are expensive, have low stability and selectivity, and usually sorption occurs by non-selective mechanisms. Various techniques have been presented for the production of homemade fibers. Most of these methods require several steps to prepare the supports to be coated. The preparation of supports for coating is time-consuming, requires numerous reagents, and does not allow the mass production of fibers. Therefore, the search is ongoing to produce new SPME fibers with selective extraction behavior, easy preparation, low cost, and less use of chemical reagents.

RESULTS

We present a straightforward, low-cost, green, and fast method to produce new SPME fibers based on microwave modification and polymerization of pencil lead support. The pencil lead structure was modified using microwave irradiation and then coated with a ketoprofen-molecularly imprinted polymer. After locating the 30 numbers of pencil lead support on the glassy holder, modification and polymerization of the supports were implemented overall at 5 min. The fibers were characterized using FT-IR, SEM, TGA, and BET analysis, showing the successful coating of the supports. The produced fibers presented selective extraction behavior for ketoprofen in the presence of similar NSAIDs with good repeatability. The detection limits for ketoprofen in plasma and urine samples were 8.25 and 16.34 ng mL, respectively. A pharmacokinetic study showed the fibers' clinical applicability, revealing a maximum plasma concentration of 15.69 μg/mL, a time to reach this concentration of 2 h, and a half-life of 2.66 h.

SIGNIFICANCE

This study represents a fast, precise, and simple method for mass-producing new SPME fibers (MIP coating) using microwave irradiation. Except for on-fiber derivatization, the introduced method doesn't need chemical reagents or extra steps. The fibers' capability was proved in urine and plasma samples for selective ketoprofen bioanalysis and pharmacokinetic study.