Fabrication of ciprofloxacin molecular imprinted polymer coating on a stainless steel wire as a selective solid-phase microextraction fiber for sensitive determination of fluoroquinolones in biological fluids and tablet formulation using HPLC-UV detection

• Novel molecularly imprinted polymer fiber coating on stainless steel was prepared.
• Fiber exhibits great extraction efficiency and high selectivity for fluoroquinolones.
• Sensitive monitoring of traces of fluoroquinolones in the biological samples.
• The proposed method has the advantage of using a small sample volume (only 25 μL of plasma or serum).
• Reducing the amount of blood collected and minimizing difficulties with some kinds of patients.

A molecularly imprinted polymer (MIP) fiber on stainless steel wire using ciprofloxacin template with a mild template removal condition was synthetized and evaluated for fiber solid phase microextraction (SPME) of fluoroquinolones (FQs) from biological fluids and pharmaceutical samples, followed by high performance liquid chromatography analysis with UV detection (HPLC-UV). The developed MIP fiber exhibited high selectivity for the analytes in complex matrices. The coating of the fibers were inspected using fourier transform infrared spectrophotometry, thermogaravimetric analysis, energy dispersive X-ray (EDX) spectroscopy as well as by scanning electron microscopy (SEM). The fiber shows high thermal stability (up to 300 °C), good reproducibility and long lifetime. The composite coating did not swell in organic solvents nor did it strip off from the substrate. It was also highly stable and extremely adherent to the surface of the stainless steel fiber. The fabricated fiber exclusively exhibited excellent extraction efficiency and selectivity for some FQs. The effective parameters influencing the microextraction efficiency such as pH, extraction time, desorption condition, and stirring rate were investigated. Under optimized conditions, the limits of detection of the four FQs ranged from 0.023–0.033 μg L−1 (S/N = 5) and the calibration graphs were linear in the concentration range from 0.1–40 μg L−1, the inter-day and intraday relative standard deviations (RSD) for various FQs at three different concentration level (n = 5) using a single fiber were 1.1–4.4% and the fiber to fiber RSD% (n = 5) was 4.3–6.7% at 5 μg L−1 of each anlyetes. The method was successfully applied for quantification of FQs in real samples including serum, plasma and tablet formulation with the recoveries between 97 to 102%.

Graphical scheme for the MIPF–SPME extraction procedure.Figure optionsDownload as PowerPoint slide