*Corresponding Author: Bareki S Batlokwa, Department of Chemical and Forensic Sciences, Botswana International University of Science and Technology, Palapye, Botswana.

Received: May 27, 2024; Published: June 18, 2024

Abstract

Monitoring the efficacy of an administered drug in a patient is a key step in patient management. It usually involves collecting a biological sample such as bile from the patient and analysing it for drug residues that may have remained after a certain drug was administered to patient and expended. Detection instruments employed for the accurate analysis of drug residues that are usually present in trace quantities are often challenged by the complex, ‘dirty’ matrix that commonly characterize biological samples from which the residues are sampled. This work considered bile, whose main constituent is cholic acid, as the biological sample. High concentration of cholic acid contributes to ion suppression during the ionization step when performing the mass spectrometry detection of the drug residues. It also masks the residues from easily being separated and detected as they exist in trace quantities in the complex matrix. Furthermore, it lowers the sensitivity of the analysing instruments, gets co-eluted with the targeted analytes, resulting in imprecise and inaccurate results. Consequently, in this work, we describe an optimal sample clean-up strategy that involved the fabrication of cholic acid (CA)-molecularly imprinted (MI) electrospun nanofiber mats that prior to instrumental analysis, selectively removed the CA that interfered with the accurate analysis of the trace drug residues. We successfully fabricated the CA-MI electrospun nanofiber mats as was demonstrated by the estimated nano sized fibrous structures of magnitude 660 nm from the SEM images. At macro level mat like structures were observed and harvested from the aluminium collector. The performance of the prepared CA-MI electrospun nanofiber mats was evaluated and was found to selectively remove 100.1% cholic acid from equimolar standard solutions consisting of cholic acid and analogous compounds, owing to the their calculated high selectivity created by the molecular imprinting technology that was employed during the synthesis and fabrication of the nanofibers that created reaction sites at molecular level, that could only fit CA as it was included as a print reagent in the spinning solution together with all other general molecular imprinting reactants and later extracted by solvent extraction leaving behind a memory for CA only in the newly prepared nanofiber mat structure. The higher CA % removal of 100.1% by the CA-MI electrospun nanofiber mats compared to the slightly lower CA %removal, 79.1% by the molecularly imprinted powder materials that were prepared for comparison, was attributed to the high surface area to volume ratio of the nano sized fiber mats that were produced by electro-spinning technology. Both, the CA-MI nanofiber mats and the CA MIP powder exhibited high selectivity since the same molecular imprinting reactants, including their quantities were used during the synthesis of both thus the same number of created selective sites but more accessibility on the nanofiber mats was realized due to their one dimensionality (thinness) compared to the thick structure of the MIP powder materials that had to be maneuverered in order to access the selective sites. This together with the large surface area to volume ratio of the nanofibers gave the CA-MI electrospun nanofiber mats the advantage in selectively removing the interfering CA in drug residue analysis from the ‘dirty’ biological samples such as bile samples prior to instrumental analysis better the MI powder.

Keywords: Molecularly Imprinted Electrospun Nanofibers; Drug Residue Analysis; Optimal Sample Clean-up; Cholic Acid; Bile

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Citation

Citation: Bareki S Batlokwa., et al. “Novel Molecularly Imprinted Nanofiber Mats for the Selective Removal of Interfering Cholic Acid Prior to Drug Residue Analysis".Acta Scientific Pharmaceutical Sciences 8.7 (2024): 55-60.

Copyright

Copyright: © 2024 Bareki S Batlokwa., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.