A novel disposable ultrasensitive sensor based on nanosized ceria uniformly loaded carbon nanofiber nanoceramic film wrapped on pencil graphite rods for electrocatalytic monitoring of a tyrosine kinase inhibitor capmatinib.

For the first time, we introduce a novel disposable and ultrasensitive sensing electrode made up of nanosized ceria uniformly loaded carbon nanofibers (CeNPs@CNF) sol-gel nanoceramic film (CF) wrapped on eco-friendly and inexpensive pencil graphite rods (PGRs) to explore their electro-catalytic detection of the anticancer drug capmatinib (CMB). The as-prepared CeNPs@CNF hybrid nanocomposite was described by XRD, SEM, TEM, HRTEM, and EDX analysis. The CV study clearly demonstrated that, the disposable CeNPs@CNF-CF/PGRE sensor exhibited excellent redox activities in the ideal probe [Fe(CN)6]3-/4-. Due to the outstanding electrochemical properties, larger electrochemically active surface area, and tremendous electro-catalytic activity of CeNPs@CNF, the reduction current of CMB on the CeNPs@CNF-CF/PGRE sensor is considerably higher than that of bare PGRE. The detection conditions, such as supporting electrolyte, pH of the buffer solution, amount of modifier, adsorption potential, and time, were studied and optimized. The sensing platform demonstrated high sensitivity (1.2 µA nM-1 cm-2), an ultralow detection limit (0.6 nM), and a wide linear range of 2.0 nM-400 nM of CMB compared to the bare PGRE. Additionally, the CeNPs@CNF-CF/PGRE sensor showed high selectivity, stability, and simple operation, which provided a promising alternative tool for fast detection of CMB in human body fluids with good recoveries.

Enhanced fluorescent detection of oxaliplatin via BSA@copper nanoclusters: a targeted approach for cancer drug monitoring.

A new fluorescence sensing approach has been proposed for the precise determination of the anti-cancer drug oxaliplatin (Oxal-Pt). This method entails synthesizing blue-emitting copper nanoclusters (CuNCs) functionalized with bovine serum albumin (BSA) as the stabilizing agent. Upon excitation at 360 nm, the resultant probe exhibits emission at 460 nm. Notably, the fluorescence response of BSA@CuNCs substantially increases upon incubation with Oxal-Pt due to multiple binding interactions between the drug and the fluorescent probe. These interactions involve hydrogen bonding, hydrophobic interaction, and the high affinity between the SH groups (cysteine residues of BSA) and platinum (in Oxal-Pt). Consequently, this interaction induces aggregation-induced emission enhancement (AIEE) of BSA@CuNCs. The probe demonstrates a broad response range from 0.08 to 140.0 µM, along with a low detection limit of 20.0 nM, determined based on a signal-to-noise ratio of 3. Furthermore, the probe effectively detects Oxal-Pt in injections, human serum, and urine samples, yielding acceptable results. This study represents a significant advancement in the development of a straightforward and efficient sensor for monitoring platinum-containing anti-cancer drugs during chemotherapy.

Gold nanoparticles anchored graphitized carbon nanofibers ionic liquid electrode for ultrasensitive and selective electrochemical sensing of anticancer drug irinotecan.

An electrochemical sensor is described for highly sensitive and selective determination of anticancer drug irinitecan (IRT). Gold nanoparticles anchored graphitized carbon nanofibers (Au@GCNFs) was prepared. Au@GCNFs was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray. The combination of high catalytic activity of the nanocomposite Au@GCNFs and the good conductivity ionic liquid [BMIM]PF6 (IL) resulted in a modified paste electrode (IL/Au@GCNFs-PE). The IL/Au@GCNFs-PE exhibits excellent electrocatalytic activity for selective determination of IRT in the presence of physiological electroactive species, such as ascorbic acid (AA), dopamine (DA), uric acid (UA), and caffeine (CAF) mixture, typically at working potential of 0.88 V vs. Ag/AgCl. The linear response ranges 4.0 nM-1.79 µM and 4.5 nM-1.57 µM with limits of detection of 1.55 nM and 1.70 nM were calculated for IRT in the absence and presence of the quaternary mixture, respectively. The sensor is reproducible and stable over four weeks, and interference by biologically essential compounds is negligible. The method was applied to the determination of IRT in pharmaceutical formulations, in spiked blood serum and urine, and in clinical patient blood. The recovery values ranged from 96.0 to 104.2%. Graphical abstract The combination of high catalytic activity of the new nanocomposite AuNPs@GCNFs with the good conductivity ionic liquid (IL) resulted to a modified paste electrode (IL/Au@GCNFs-PE). The novel sensor was successfully applied for the sensitive and selective detection of IRT in biological samples in the presence of quaternary ascorbic acid (AA), dopamine (DA), uric acid (UA), and caffeine (CAF) mixture.

A novel megestrol acetate electrochemical sensor based on conducting functionalized acetylene black-CeO2NPs nanohybrids decorated glassy carbon microspheres.

For the first time, megestrol acetate (MGA), a synthetic progestin with therapeutic use in breast cancer, is electrochemically studied to propose a new electroanalytical alternative for its detection in real samples. In the present work, a novel electrochemical sensor based on functionalized acetylene black-CeO2NPs nanohybrids modified glassy carbon microspheres paste electrode (FAB-CeO2NPs/GCMPE) was successfully fabricated and used for sensitive determination of MGA. The modified electrode has been characterized using scanning electron microscope (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electrocatalytic reduction of MGA using FAB-CeO2NPs/GCMPE was carried out via CV and square wave voltammetry (SWV). By employing FAB-CeO2NPs/GCMPE, the SWV signal of MGA reduction was 8 fold higher than the bare GCMPE. A wide concentration range from 4.20 × 10-8 to 1.13 × 10-6 M with the low LOD of 1.30 nM for MGA was achieved. The practical analytical utilities of the prospective FAB-CeO2NPs/GCMPE sensor were demonstrated successfully by the detection of MGA in Megace tablets, human serum and urine samples obtained from healthy and patient volunteers after oral administration of 160 mg Megace tablets. HPLC method was also developed for comparison with the electroanalytical method.

Comparative studies on the interaction of anticancer drug irinotecan with dsDNA and ssDNA.

A systematic comparative study on the binding of anticancer drug irinotecan (Irino) with dsDNA and ssDNA was investigated in phosphate buffer solutions using voltammetric and spectroscopic methods. The voltammetric results show that the Irino molecule, acting as an intercalator, is inserted into the base stacking domain of the DNA double helix and the strength of interaction is independent of the ionic strength. The hyperchromic effect observed in the UV-visible spectra of Irino in the presence of dsDNA provided the evidence for the intercalation of the drug chromophore with dsDNA base. The interaction mode of Irino molecules with ssDNA is electrostatic attraction via negative phosphate on the exterior of the ssDNA with Irino. The binding constants, stoichiometric coefficients and thermodynamic parameters of Irino-dsDNA and Irino-ssDNA complexes were evaluated. The magnitude of changes in ΔG o, ΔH o and ΔS o indicated that the binding process of Irino with ssDNA was more affected than that with dsDNA. The decrease of the peak current of Irino was proportional to DNA concentration, which was applied for determination of dsDNA and ssDNA concentration. The achieved limits of detection of dsDNA and ssDNA were 5.49 × 10-7 and 1.87 × 10-7 M, respectively.

Binding mode and thermodynamic studies on the interaction of the anticancer drug dacarbazine and dacarbazine-Cu(II) complex with single and double stranded DNA.

The binding mode and thermodynamic characteristics of the anticancer drug dacarbazine (Dac) with double and single stranded DNA were investigated in the absence and presence of Cu(II) using cyclic voltammetry, square wave voltammetry and fluorescence spectroscopy. The interaction of Dac and Dac-Cu(II) complex with dsDNA indicated their intercalation into the base stacking domain of dsDNA double helix and the strength of interaction is independent on the ionic strength. The interaction of Dac with dsDNA in the presence of Cu(II) leads to a much stronger intercalation. The interaction mode of Dac molecules with ssDNA is electrostatic attraction via negative phosphate on the exterior of the ssDNA with Dac. The binding constants, stoichiometric coefficients and thermodynamic parameters of Dac and Dac-Cu(II) complex with dsDNA and ssDNA were evaluated. Comparison of the mode interaction of Dac with dsDNA and ssDNA was discussed. The decrease of peak current of Dac was proportional to DNA concentration, which was applied for determination of dsDNA and ssDNA concentration.