Fabrication of a novel impedimetric biosensor for label free detection of DNA damage induced by doxorubicin

Mechanisms underlying dose-limiting toxicities of conventional chemotherapeutic agents

Dose-limiting toxicities (DLTs) are severe adverse effects that define the maximum tolerated dose of a cancer drug. In addition to the specific mechanisms of each drug, common contributing factors include inflammation, apoptosis, ion imbalances, and tissue-specific enzyme deficiencies. Among various DLTs are bleomycin-induced pulmonary fibrosis, doxorubicin-induced cardiomyopathy, cisplatin-induced nephrotoxicity, methotrexate-induced hepatotoxicity, vincristine-induced neurotoxicity, paclitaxel-induced peripheral neuropathy, and irinotecan, which elicits severe diarrhea. Currently, specific treatments beyond dose reduction are lacking for most toxicities. Further research on cellular and molecular pathways is imperative to improve their management. This review synthesizes preclinical and clinical data on the pharmacological mechanisms underlying DLTs and explores possible treatment approaches. A comprehensive perspective reveals knowledge gaps and emphasizes the need for future studies to develop more targeted strategies for mitigating these dose-dependent adverse effects. This could allow the safer administration of fully efficacious doses to maximize patient survival.

Integration of Glutamate Dehydrogenase and Nanoporous Gold for Electrochemical Detection of Glutamate

Glutamate, a non-essential amino acid produced by fermentation, plays a significant role in disease diagnosis and food safety. It is important to enable the real-time monitoring of glutamate concentration for human health and nutrition. Due to the challenges in directly performing electrochemical oxidation-reduction reactions of glutamate, this study leverages the synergistic effect of glutamate dehydrogenase (GLDH) and nanoporous gold (NPG) to achieve the indirect and accurate detection of glutamate within the range of 50 to 700 μM by measuring the generated quantity of NADH during the enzymatic reaction. The proposed biosensor demonstrates remarkable performance characteristics, including a detection sensitivity of 1.95 μA mM-1 and a limit of detection (LOD) of 6.82 μM. The anti-interference tests indicate an average recognition error ranging from -3.85% to +2.60%, spiked sample recovery rates between 95% and 105%, and a relative standard deviation (RSD) of less than 4.97% for three replicate experiments. Therefore, the GLDH-NPG/GCE biosensor presented in this work exhibits excellent accuracy and repeatability, providing a novel alternative for rapid glutamate detection. This research contributes significantly to enhancing the precise monitoring of glutamate concentration, thereby offering more effective guidance and control for human health and nutrition.

Impedimetric DNA Sensors for Epirubicin Detection Based on Polythionine Films Electropolymerized from Deep Eutectic Solvent

An electrochemically active polymer, polythionine (PTN), was synthesized in natural deep eutectic solvent (NADES) via multiple potential scans and characterized using cyclic voltammetry and electrochemical impedance spectroscopy (EIS). NADES consists of citric acid monohydrate, glucose, and water mixed in the molar ratio of 1:1:6. Electrodeposited PTN film was then applied for the electrostatic accumulation of DNA from salmon sperm and used for the sensitive detection of the anticancer drug epirubicin. Its reaction with DNA resulted in regular changes in the EIS parameters that made it possible to determine 1.0-100 µM of epirubicin with the limit of detection (LOD) of 0.3 µM. The DNA sensor developed was successfully applied for the detection of epirubicin in spiked samples of artificial and natural urine and saliva, with recovery ranging from 90 to 109%. The protocol of the DNA sensor assembling utilized only one drop of reactants and was performed with a minimal number of steps. Together with a simple measurement protocol requiring 100 µL of the sample, this offers good opportunities for the further use of the DNA sensor in monitoring the drug level in biological samples, which is necessary in oncology treatment and for the pharmacokinetics studies of new antitumor drugs.

Anti-Biofouling Electrochemical Sensor Based on the Binary Nanocomposite of Silica Nanochannel Array and Graphene for Doxorubicin Detection in Human Serum and Urine Samples

A disposable and portable electrochemical sensor was fabricated by integrating vertically-ordered silica mesoporous films (VMSF) and electrochemically reduced graphene (ErGO) on a screen-printed carbon electrode (SPCE). Such VMSF/ErGO/SPCEs could be prepared by a simple and controllable electrochemical method. Stable growth of VMSF on SPCE could be accomplished by the introduction of an adhesive ErGO nanolayer owing to its oxygen-containing groups and two-dimensional (2D) planar structure. An outer VMSF layer acting as a protective coating is able to prevent the leakage of the inner ErGO layer from the SPCE surface. Thanks to the electrostatic permselectivity and anti-fouling capacity of VMSF and to the good electroactive activity of ErGO, binary nanocomposites of VMSF and ErGO endow the SPCE with excellent analytical performance, which could be used to quantitatively detect doxorubicin (DOX) in biological samples (human serum and urine) with high sensitivity, good long-term stability, and low sample amounts.

CISS-Based Label-Free Novel Electrochemical Impedimetric Detection of UVC-Induced DNA Damage

In this work, we demonstrate chiral-induced spin selectivity (CISS)-based label-free electrochemical impedimetric detection of radiation-induced DNA damage using the electrons' spin as a novel tool of sensing. For this, self-assembled monolayers (SAMs) of short ds-DNA (of length 7.14 nm) are prepared on arrays of multilayer thin film devices comprising a gold overlay (500 μm diameter with 10 nm thickness) on a nickel thin film (100 nm) fabricated by the physical vapor deposition technique. Subsequently, the SAMs of ds-DNA are exposed to ultraviolet C (UVC) radiation for a prolonged period of 8 h to induce structural perturbations in DNA. The susceptibility of DNA to radiation-induced damage was probed by recording the spin-dependent electrochemical impedimetric spectra, wherein a continuous sinusoidal wave of the amplitude of 10 mV was superimposed on DC bias in the frequency range of 10⁰-10⁵ Hz, with simultaneous spin injection through the attached DNA. The inherent correlation between the charge-transfer resistance (R _ct) and the spin selectivity of electrons through DNA was taken into account for the detection of DNA damage for the first time with a limit of detection achieved up to 10 picomolar concentrations of DNA. As the spin-polarized electrons directly probe the structural symmetry, it is robust against perturbation from electronic signals usually found in conventional electrochemical biosensors.

Bioinorganic Synthesis of Sodium Polytungstate/Polyoxometalate in Microbial Kombucha Media for Precise Detection of Doxorubicin

In this study, we have developed a new platform of polyoxometalate as a biocompatible and electrosensitive polymeric biosensor for the accurate detection of doxorubicin. For this purpose, we used a green synthesis approach using tartaric acid, glutamic acid, and kombucha solvent. Thanks to its bioinorganic components, the biogenic approach can chemically modify and improve the performance of the biosensor, which was experimentally confirmed. Our results showed excellent sensitivity (175.72 μA·μM⁻¹·cm⁻²), low detection limit (DL, 8.12 nM), and low quantification limit (QL, 0.056 μM) when the newly developed biosensor was used. The results also show that the biosynthesized biosensor has improved performance in detecting DOX in the biological fluid with an accuracy of more than 99% depending on the components used, which underlines the high efficiency of the biosensor produced. Considering the body's physiological condition, the biosensor fabricated as a biocompatible component can show high efficiency. Therefore, its applicability for clinical use still needs to be studied in detail.

Impedance Analysis of Electrochemical Systems

Interpretation of impedance spectroscopy data requires both a description of the chemistry and physics that govern the system and an assessment of the error structure of the measurement. The approach presented here includes use of graphical methods to guide model development, use of a measurement model analysis to assess the presence of stochastic and bias errors, and a systematic development of interpretation models in terms of the proposed reaction mechanism and physical description. Application to corrosion, batteries, and biological systems is discussed, and emerging trends in interpretation and implementation of impedance spectroscopy are presented.

Doxorubicin and Trifolium pratense L. (Red clover) extract synergistically inhibits brain and lung metastases in 4T1 tumor-bearing BALB/c mice

Trifolium pratense L. (Red clover-T. pratense) commonly consumed as a healthy beverage has been demonstrated to have various biological activities including antioxidant and anticancer effects. The aim of this study was to investigate the antimetastasis effects of doxorubicin (DOX) and T. pratense extract in 4T1 tumor-bearing BALB/c mice. In this study, 56 female BALB/c mice were randomly divided into seven groups (n = 8/group) to receive DOX and T. pratense extract in three different doses (100, 200, and 400 mg/kg/day) for 35 days. On day 36 after starting treatments, serum cytokines (IL-8 and IL-6) were measured. Immunohistochemical (IHC) staining was performed for GATA-3 in the brain and lung, and for CK5/6 in tumor tissues. Metastasis-related gene (matrix metalloproteinase-2 [MMP-2] and sirtuin-1 [SIRT-1]) expressions were also measured by real-time PCR. Our results showed that cotreatment with DOX and T. pratense extract improved stereological parameters (i.e., reduction in the volume of metastatic tumors) in the lung and brain and decreased the serum levels of inflammatory cytokines (IL-8 and IL-6). DOX and T. pratense extract synergistically down-regulated MMP-2 and up-regulated SIRT-1 genes, decreased the number of CK5/6-positive cells in tumor tissues, and inhibited metastasis of GATA-3-positive cells into the lung and brain. The combination of T. pratense extract and DOX synergistically inhibited the metastasis of 4T1 xenograft cells in a dose-dependent manner.

Performance of chitosan polymer as platform during sensors fabrication and sensing applications

Chitosan is an important polymer produced from deacetylation of several sea and insects crusts. Due to its environmental fate and biological biocompatibility, it can be used in several biological and environmental applications. Sensing of biological compounds in human bodies and also in serum, blood, and different body fluids has found an important application instead of direct determination of the body fluids using complicated tools. Sensing process of biological compounds during bio-analysis of the biological systems, especially human fluids lack of several parameters including: high sensitivity, repeatability, speed of analysis and biocompatibility of the used analytical methods, especially in-vivo analysis. That was due to the time between sample handling and sample determination can change various components and concentrations of the bio-compounds. The need for in-situ analysis was directed the researchers for biosensors to overcome the upgrading problems of bio-analysis. Biosensors were the future of this issue. Chitosan can reserve as great platform for fabrication of different sensors to determine the elements, compounds and body bioactive compounds. The presence of different terminal amino and hydroxyl groups within chitosan framework facilitates the immobilization of different biomarkers to be used as sensing elements for the determined compounds. The use of chitosan as sensors platform was enhanced by using chitosan in its nanoforms.

Novel green synthesis and antioxidant, cytotoxicity, antimicrobial, antidiabetic, anticholinergics, and wound healing properties of cobalt nanoparticles containing Ziziphora clinopodioides Lam leaves extract

The aim of the experiment was a green synthesis of cobalt nanoparticles from the aqueous extract of Ziziphora clinopodioides Lam (CoNPs) and assessment of their cytotoxicity, antioxidant, antifungal, antibacterial, and cutaneous wound healing properties. The synthesized CoNPs were characterized using different techniques including UV-Vis., FT-IR spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). According to the XRD analysis, 28.19 nm was measured for the crystal size of NPs. TEM and SEM images exhibited a uniform spherical morphology and average diameters of 29.08 nm for the biosynthesized nanoparticles. Agar diffusion tests were done to determine the antibacterial and antifungal characteristics. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) were specified by macro-broth dilution assay. CoNPs indicated higher antibacterial and antifungal effects than many standard antibiotics (p ≤ 0.01). Also, CoNPs prevented the growth of all bacteria at 2-4 mg/mL concentrations and removed them at 2-8 mg/mL concentrations (p ≤ 0.01). In the case of antifungal effects of CoNPs, they inhibited the growth of all fungi at 1-4 mg/mL concentrations and destroyed them at 2-16 mg/mL concentrations (p ≤ 0.01). The synthesized CoNPs had great cell viability dose-dependently and indicated this method was nontoxic. DPPH free radical scavenging test was done to assess the antioxidant potentials, which revealed similar antioxidant potentials for CoNPs and butylated hydroxytoluene. In vivo experiment, after creating the cutaneous wound, the rats were randomly divided into six groups: untreated control, treatment with Eucerin basal ointment, treatment with 3% tetracycline ointment, treatment with 0.2% Co(NO₃)₂ ointment, treatment with 0.2% Z. clinopodioides ointment, and treatment with 0.2% CoNPs ointment. These groups were treated for 10 days. For histopathological and biochemical analysis of the healing trend, a 3 × 3 cm section was prepared from all dermal thicknesses at day 10. Use of CoNPs ointment in the treatment groups substantially raised (p ≤ 0.01) the wound contracture, hydroxyl proline, hexosamine, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate and remarkably decreased (p ≤ 0.01) the wound area, total cells, neutrophil, and lymphocyte compared to other groups. In conclusion, CoNPs can be used as a medical supplement owing to their non-cytotoxic, antioxidant, antibacterial, antifungal, and cutaneous wound healing effects. Additionally, the novel nanoparticles (Co(NO₃)₂ and CoNPs) were good inhibitors of the α-glycosidase, and cholinesterase enzymes.

An elegant technology for ultrasensitive impedimetric and voltammetric determination of cholestanol based on a novel molecularly imprinted electrochemical sensor

In this work, a novel molecularly imprinted electrochemical sensor (MIES) has been fabricated based on electropolymerization of a molecularly imprinted polymer (MIP) onto a glassy carbon electrode (GCE) modified with gold-palladium alloy nanoparticles (AuPd NPs)/polydopamine film (PDA)/multiwalled carbon nanotubes-chitosan-ionic liquid (MWCNTs-CS-IL) for voltammetric and impedimetric determination of cholestanol (CHO). Modifications applied to the bare GCE formed an excellent biocompatible composite film which was able to selectively detect CHO molecules. Modifications applied to the bare GCE were characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (SEM). Under optimal experimental conditions, the sensor was able to detect CHO in the range of 0.1-60 pM and 1-50 pM by EIS and DPV, respectively. Moreover, the sensor showed high sensitivity, selectivity, repeatability, reproducibility, low interference and good stability towards CHO determination. Our records confirmed that the sensor was successfully able to the analysis real samples for determination of CHO.

Biosensor of Inflammation Biomarkers Based on Electrical Bioimpedance Analysis on Immobilized DNA Without Chemical Modification

The development of biosensors to identify molecular markers or specific genes is fundamental for the implementation of new techniques that allow the detection of specific Deoxyribonucleic acid (DNA) sequences in a fast, economic and simple way. Different detection techniques have been proposed in the development of biosensors. Electrical Bioimpedance Spectroscopy (EBiS) has been used for diagnosis and monitoring of human pathologies, and is recognized as a safe, fast, reusable, easy and inexpensive technique. This study proves the development of a complementary DNA (cDNA) biosensor based on measurements of EBiS and DNA's immobilization with no chemical modifications. The evaluation of its potential utility in the detection of the gene expression of three inflammation characteristic biomarkers (NLRP3, IL-1β and Caspase 1) is presented. The obtained results demonstrate that EBiS can be used to identify different gene expression patterns, measurements that were validated by Quantitative Polymerase Chain Reaction (qPCR). These results indicate the technical feasibility for a biosensor of specific genes through bioimpedance measurements on the immobilization of cDNA.

Developing an elegant and integrated electrochemical-theoretical approach for detection of DNA damage induced by 4-nonylphenol

In this work, a novel biosensor was fabricated for detection of DNA damage induced by 4-nonylphenol (NP) and also determination of NP. To achieve this goal, a glassy carbon electrode (GCE) was modified with chitosan (Chit), gold nanoparticles (Au NPs) and DNA-multiwalled carbon nanotubes (DNA-MWCNTs). Then, the DNA-MWCNTs/Au NPs/Chit/GCE was incubated with methylene blue (MB) to obtain MB-DNA-MWCNTs/Au NPs/Chit/GCE in which MB was used as the redox indicator. The modifications applied to the GCE were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopic (EDS) and theoretical evidence. MB is a derivative of anthraquinone which can intercalate into double helix structure of DNA. By treating MB-DNA-MWCNTs/Au NPs/Chit/GCE with NP, a higher R _ct was observed because the insertion of the NP may result in a more negative charge environment on the DNA surface which hinders accessibility of [Fe(CN)₆]^3-/4- anion to the electrode surface. Change in the EIS response of the biosensor in the presence of NP was used to develop a novel system for monitoring the DNA damage induced by NP. The EIS technique was also used to develop a sensitive electroanalytical method for determination of NP.

Novel synthesis of Falcaria vulgaris leaf extract conjugated copper nanoparticles with potent cytotoxicity, antioxidant, antifungal, antibacterial, and cutaneous wound healing activities under in vitro and in vivo condition

Facile green synthesis of copper nanoparticles from different biological procedures has been indicated, but among all, biosynthesis of copper nanoparticles from medicinal plants is considered as the most suitable method. The use of medicinal plant material increases the therapeutical effects of copper nanoparticles. The aim of this study was green synthesis of copper nanoparticles from aqueous extract of Falcaria vulgaris leaf (CuNPs) and assessment of their cytotoxicity, antioxidant, antifungal, antibacterial, and cutaneous wound healing properties. These nanoparticles were characterized by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM) analysis. The synthesized CuNPs had great cell viability dose-dependently (Investigating the effect of the CuNPs on human umbilical vein endothelial cell (HUVEC) line) and indicated this method was nontoxic. Also, 2,2-diphenyl-1-picrylhydrazyl (DPPH) test was done to assess the antioxidant activities, which indicated similar antioxidant potentials for CuNPs and butylated hydroxytoluene. In part of cutaneous wound healing property of CuNPs, after creating the cutaneous wound, the rats were randomly divided into six groups: treatment with 0.2% CuNPs ointment, treatment with 0.2% CuSO₄ ointment, treatment with 0.2% F. vulgaris ointment, treatment with 3% tetracycline ointment, treatment with Eucerin basal ointment, and untreated control. These groups were treated for 10 days. Treatment with CuNPs ointment remarkably increased (p ≤ .01) the wound contracture, vessel, hexosamine, hydroxyl proline, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate and substantially reduced (p ≤ .01) the wound area, total cells, neutrophil, and lymphocyte compared to other groups. In antibacterial and antifungal parts of this research, the concentration of CuNPs with minimum dilution and no turbidity was considered minimum inhibitory concentration (MIC). To determine minimum fungicidal concentration (MFC) and minimum bactericidal concentration (MBC), 60 μL MIC and three preceding chambers were cultured on Sabouraud Dextrose Agar and Muller Hinton Agar, respectively. The minimum concentration with no fungal and bacterial growth were considered MFC and MBC, respectively. CuNPs inhibited the growth of all fungi at 2-4 mg/mL concentrations and removed them at 4-8 mg/mL concentrations (p ≤ .01). In case of antibacterial effects of CuNPs, they inhibited the growth of all bacteria at 2-8 mg/mL concentrations and removed them at 4-16 mg/mL concentrations (p ≤ .01). The results of XRD, FT-IR, UV, TEM, and FE-SEM confirm that the aqueous extract of F. vulgaris leaf can be used to yield copper nanoparticles with notable amount of antioxidant, antifungal, antibacterial, and cutaneous wound healing potentials without any cytotoxicity. Further clinical trials are necessary for confirmation these therapeutical effects of CuNPs in human.

Fabrication of a novel biosensor for biosensing of bisphenol A and detection of its damage to DNA

In this work, a novel electrochemical biosensor has been fabricated based on step-by-step modification of a glassy carbon electrode (GCE) with methylene blue (MB)-DNA/multiwalled carbon nanotubes (MWCNTs)-chitosan (CS)/palladium nanoparticles (Pd NPs)/fullerene C₆₀ (C₆₀) for voltammetric and impedimetric detection of DNA damage induced by bisphenol A (BPA). Modifications applied to the GCE were characterized by cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy. The EIS and DPV responses of the biosensor were increased and decreased, respectively, by the DNA damage induced by BPA which led us to develop novel systems for detection of DNA damage. Our records confirmed that the biosensor was able to rapid and sensitive detection of DNA damage induced by BPA. Finally, according to the developed systems for detection of DNA damage, we have developed voltammetric and impedimetric methods for determination of BPA.