A Carbon Ionic Liquid Paste Sensor Modified with Lanthanum Nanorods /MWCNTs/Nafion Hybrid Composite for Carbamazepine Screening in Biological and Pharmaceutical Media

Abstract

In this original paper, a new electrochemical sensor for carbamazepine (CBZ) was developed. First, lanthanum nanorods (LaNRs) were synthesized by a simple microemulsion method. Then, a nanocomposite consist of lanthanum nanorods, multiwalled carbon nanotubes (MWCNTs), and nafion (LaNRs/MWCNTs/Nafion) was prepared and deposited at the surface of the carbon ionic liquid paste electrode (CILPE). X‐ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersion spectroscopy (EDS), and scanning electron microscopy (SEM) were used to characterize the structure of synthesized LaNRs and the surface morphology of the modified electrode. Also, electrochemical methods such as cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS) were utilized to investigate the performance of the proposed electrode. Under the optimal conditions, a linear relationship of the electrical signal versus the concentration of CBZ was obtained in the range from 0.06 μM to 20 μM with a detection limit (LOD) of 0.006 μM and quantification limit (LOQ) of 0.02 μM. Eventually, the fabricated sensor was satisfactorily applied for rapid and accurate determination of CBZ in real samples.

(Bio)Sensing Strategies Based on Ionic Liquid-Functionalized Carbon Nanocomposites for Pharmaceuticals: Towards Greener Electrochemical Tools

“…After modification of a GCE, further nanostructuration occurred through electrodeposition of nickel oxide nanoparticles at a fixed potential of -0.8 V. Under DPV analysis at an optimum pH of 7, the sensor presented similar results for both drugs with linear range, sensitivity, and LOD of 0.5 to 67 μmol L −1 , 0.52 μA μmol −1 L, and 0.052 μmol L −1 , respectively, for clozapine and 0.21 to 85 μmol L −1 , 0.53 μA μmol −1 L, and 0.047 μmol L −1 , respectively for sertraline [ 61 ]. In a different approach, Tarahomi et al [ 62 ] applied both IL and MWCNT in an electrode modification intended for carbamazepine though not promoting a direct mixture between these two materials in a composite. Specifically, a CPE was first assembled by mixing graphite, paraffin, and the IL 1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide (BMIM.TSFI).…”

“…Its surface was then modified by dropcast with the composite mixture of MWCNT and previously synthesized lanthanum nanorods (LaNRs), followed by a final film of Nafion. Although laborious, the sensor reached a low LOD of 0.006 μmol L −1 in optimum acidic conditions (pH 2), also revealing great stability after 4 weeks by maintaining 98% of the response [ 62 ].…”