A novel fluorescent probe based imprinted polymer-coated magnetite for the detection of imatinib leukemia anti-cancer drug traces in human plasma samples

Myeloid leukemia is a chronic cancer, which associated with abnormal BCR-ABL tyrosine kinase activity. Imatinib (IMB) acts as a tyrosine kinase inhibitor and averts tumor growth in cancer cells by controlling cell division, so it is urgent to develop an effective assay to detect and monitor its IMB concentration. Therefore, an innovative fluorescent biomimetic sensor is a promising sensing material that constructed for the efficient recognition of IMB and displays excellent selectivity and sensitivity stemming from molecularly imprinted polymer@Fe3O4 (MIP@Fe3O4). The detection strategy depends on the recognition of IMB molecules at the imprinted sites in the presence of coexisting molecules, which are then transferred to the fluorescence signal. The synthesized MIP@Fe3O4 was characterized using Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Furthermore, computational studies of the band gap (EHOMO-ELUMO) of the monomers, IMB, and their complexes were performed. These results confirmed that the copolymer is the most appropriate and has high stability (Binding energy; 0.004 x 10-19 KJ) and low reactivity. A comprehensive linear response over IMB concentrations from 5 × 10-6 mol/L to 8 × 10-4 mol/L with a low detection limit of 9.3 × 10-7 mol/L was achieved. Furthermore, the proposed technique displayed long-term stability (over 2 months), high intermediate precision (RSD<2.1 %), good reproducibility (RSD <1.9 %), and outstanding selectivity toward IMB over analogous molecules with similar chemical and spatial structure (no interference by 100 to 150-fold of the competitors). Owing to these merits, the proposed fluorescence sensor was utilized to detect IMB in drug tablets and human plasma, and satisfactory results (99.3-100.4 %) were obtained. Thus, the synthesized fluorescence sensor is a promising platform for IMB sensing in various applications.

A rational study of transduction mechanisms of different materials for all solid contact-ISEs

The new era of solid contact ion selective electrodes (SC-ISEs) miniaturized design has received an extensive amount of concern. Because it eliminated the requirement for ongoing internal solution composition optimization and created a two-phase system with stronger detection limitations. Herein, the determination of venlafaxine HCl is based on a comparison study between different ion- to electron transduction materials (such as; multiwalled carbon nanotubes (MWCNTs), polyaniline (PANi), and ferrocene) and illustrating their mechanisms in their applied sensors. Their different electrochemical features (such as bulk resistance (Rb**), double-layer capacitance (Cdl), geometric capacitance (Cg), and specific capacitance (Cp)) were evaluated and discussed by using the Electrochemical Impedance Spectroscopy (EIS), Chronopotentiometry (CP), and Cyclic Voltammetry (CV) experiments. The results indicated that each transducer's influence on the proposed sensor's electrochemical characteristics is determined by their unique chemical and physical properties. The electrochemical features vary for different solid contact materials used in transduction mechanisms. The results confirm that the MWCNT sensor revealed the best electrochemical behavior with the potentiometric response of a near-Nernestian slope of 56.1 ± 0.8 mV/decade with detection limits of 3.8 × 10-6 mol/L (r2 = 0.999) and a low potential drift (∆E/∆t) of 34.6 µV/s. Also, the selectivity study was performed in the presence of different interfering species either in single or complex matrices. This demonstrates excellent selectivity, stability, conductivity, and reliability as a VEN-TPB ion pair sensor for accurately measuring VEN in its various formulations. The proposed method was compared to HPLC reported technique and confirmed no significant difference between them. So, the proposed sensors fulfill their solutions' demand features for VEN appraisal.

Evaluation of the effect of direct-acting antiviral agents on melatonin level and lipid peroxidation in chronic hepatitis C patients

Background: Oxidative stress and its end products, such as malondialdehyde (MDA) play a leading role in the pathogenesis of hepatitis C. Melatonin is a hormone that helps regulate circadian rhythms, which likely play a role in infectious diseases in terms of susceptibility, clinical expression, and outcome. Objective: The present study was conducted to assess serum malondialdehyde and melatonin levels in patients with chronic hepatitis C infection before and after the intake of direct-acting antivirals. Method: Forty hepatitis C patients were the subjects of this study. While ten healthy volunteers who matched in age and socioeconomic status served as the control subjects. Malondialdehyde and melatonin were assayed in the serum of the three groups, and the results were statistically analyzed. Results: Hepatitis C patients had significantly higher malondialdehyde (p < 0.001) but significantly lower melatonin (p < 0.001) as compared to the healthy controls. After 12 weeks of treatment with direct-acting antivirals, the malondialdehyde level decreased significantly (p < 0.001) and the melatonin level increased significantly (p < 0.001). A significant negative correlation between malondialdehyde and melatonin was observed. Conclusion: The present findings suggest that treatment of hepatitis C patients with Direct-acting antivirals improves liver function parameters and antioxidant profiles.

Synthesis and numerical simulation of formamidinium-based perovskite solar cells: a predictable device performance at NIS-Egypt

Formamidinium lead triiodide (δ-FAPbI₃)-based perovskite solar cells showed remarkable potential as light harvesters for thin-film photovoltaics. Herein, the mechanochemical synthesis of δ-FAPbI₃, MAPbI₃, and mixed-cation FA_1-xMA_xPbI₃ with (x = 0.3, 0.5, and 0.7) perovskite materials were prepared as a novel green chemistry method for scaling up production. Crystallinity, phase identification, thermal stability, optoelectronic properties, and nanoscale composition are discussed. The results demonstrated that the prepared mixed-cation samples are enhanced in the visible absorption region and are consistent with previous works. The crystal structure of δ-FAPbI₃ was altered to a cubic structure due to the change in FA-cation. Moreover, the performance of [Formula: see text]-FA-based perovskites was investigated using the Solar Cell Capacitance Simulator (SCAPS-1D) software. The validity of the device simulation was confirmed by comparing it to real-world devices. The photovoltaic characteristics and impact of absorber thickness on device performance were explained. The [Formula: see text]-FA-based solar cell with a 50% MA-doped molar ratio shows a better performance with an efficiency of 26.22% compared to 8.43% for δ-FAPbI₃. The outcome results of this work confirm the beneficial effect of mixed cations on device operation and advance our knowledge of the numerical optimization of perovskite-based solar cells.

Fabrication and characterization of electrospun nanofibers using biocompatible polymers for the sustained release of venlafaxine

Recently, drug-controlled release nanotechnology has gained special attention in biomedicine. This work focuses on developing novel electrospun polymeric nanofibers (NFs) for buccal delivery of VEN to avoid the hepatic metabolism and enzymatic degradation in the GIT and develop an effective control of drug release. The optimized NFs were obtained by blending polylactic acid (PLA), and poly (ɛ-caprolactone) (PCL) fixed at a ratio of 1:1. It was characterized for morphology, drug-loading, FTIR, XRD, DSC, and in vitro drug release. Ex vivo permeability of the blend NFs was assessed using chicken pouch mucosa compared to VEN suspension, followed by histopathological examination. Further, the cytotoxic effect in three different cell lines using WST-1 assay. SEM morphologies refer to defect-free uniform NFs of PLA, PCL, and PLA/PCL mats. These fibers had a diameter ranging from 200 to 500 nm. The physico-thermal characterization of NFs depicted that the drug was successfully loaded and in an amorphous state in the PLA/PCL NFs. In vitro release of NFs substantiated a bi-phasic profile with an initial burst release of about 30% in the initial 0.5 h and a prolonged cumulative release pattern that reached 80% over 96 h following a non-Fickian diffusion mechanism. Ex vivo permeation emphasizes the major enhancement of the sustained drug release and the noticeable decrease in the permeability of the drug from NFs. Cytotoxicity data found that IC₅₀ of VEN alone was 217.55 μg/mL, then VEN-NFs recorded an IC₅₀ value of 250.62 μg/mL, and plain NFs showed the lowest toxicity and IC₅₀ 440.48 μg/mL in oral epithelial cells (OEC). Histopathology and cell toxicity studies demonstrated the preserved mucosal architecture and the preclinical safety. The developed PLA/PCL NFs can be promising drug carriers to introduce a step-change in improved psychiatric treatment healthcare.

Imprinted Polymeric Beads-Based Screen-Printed Potentiometric Platforms Modified with Multi-Walled Carbon Nanotubes (MWCNTs) for Selective Recognition of Fluoxetine

Herein, we present a new validated potentiometric method for fluoxetine (FLX) drug monitoring. The method is based on the integration of molecular imprinting polymer (MIP) beads as sensory elements with modified screen-printed solid contact ion-selective electrodes (ISEs). A multi-walled carbon nanotube (MWCNT) was used as a nanomaterial for the ion-to-electron transduction process. The prepared MIP beads depend on the use of acrylamide (AAm) and ethylene glycol dimethacrylic acid (EGDMA) as a functional monomer and cross-linker, respectively. The sensor revealed a stable response with a Nernstian slope of 58.9 ± 0.2 mV/decade and a detection limit of 2.1 × 10⁻⁶ mol/L in 10 mmol/L acetate buffer of pH 4.5. The presented miniaturized sensors revealed good selectivity towards FLX over many organic and inorganic cations, as well as some additives encountered in the pharmaceutical preparations. Repeatability, reproducibility and stability have been studied to evaluate the analytical features of the presented sensors. These sensors were successfully applied for FLX assessment in different pharmaceutical formulations collected from the Egyptian local market. The obtained results agreed well with the acceptable recovery percentage and were better than those obtained by other previously reported routine methods.