NanoMIP-Based Solid Phase Extraction of Fluoroquinolones from Human Urine: A Proof-of-Concept Study

Abstract

NanoMIPs that are prepared by solid phase synthesis have proven to be very versatile, but to date only limited attention has been paid to their use in solid phase extraction. Thus, since nanoMIPs show close similarities, in terms of binding behavior, to antibodies, it seems relevant to verify if it is possible to use them as mimics of the natural antibodies that are used in immunoextraction methods. As a proof-of-concept, we considered prepared nanoMIPs against fluoroquinolone ciprofloxacin. Several nanoMIPs were prepared in water with polymerization mixtures of different compositions. The polymer with the highest affinity towards ciprofloxacin was then grafted onto a solid support and used to set up a solid phase extraction–HPLC method with fluorescence detection, for the determination of fluoroquinolones in human urine. The method resulted in successful selection for the fluoroquinolone antibiotics, such that the nanoMIPs were suitable for direct extraction of the antibiotics from the urine samples at the µg mL−1 level. They required no preliminary treatment, except for a 1 + 9 (v/v) dilution with a buffer of pH 4.5 and they had good analyte recovery rates; up to 85% with precision in the range of 3 to 4.5%, without interference from the matrix. These experimental results demonstrate, for the first time, the feasibility of the use of nanoMIPs to develop solid phase extraction methods.

Molecularly Imprinted Polymers: Selective Extraction Materials for Sample Preparation

“…NanoMIPs have proven to be very versatile, but to date only limited attention has been paid to their use in solid-phase extraction; thus, the paper by Chiarello et al [12] of the present Special Issue focuses on the ability of nanoMIPs to extract fluoroquinolone antibiotics from human urine by MISPE. Several nanoMIPs were prepared in water with polymerization mixtures of different compositions, and the polymer with the highest affinity towards ciprofloxacin was then grafted onto a solid support and used to set up a solid-phase extraction-HPLC method with fluorescence detection.…”

Separation Methods in Biomedical Analysis, a Booming Field

“…An interesting proposal is the nanostructuration of extraction supports. These devices allow for very specific extractions, for instance, thiol analysis using gold nanoparticles [19], drug extraction using silver nanoparticles [20], or the extraction of heavy metals using quantum dots [21]; other types of nanoparticles are also being studied [22]. Miniaturization and the use of nanomaterials allow to increase the extraction efficiency thanks to the higher specific surface of the support and thus to the surface available to interact with the targeted molecules.…”