Electrochemical sensing of doxorubicin in unprocessed whole blood, cell lysate, and human plasma samples using thin film of poly-arginine modified glassy carbon electrode

Use of gold/iron metal-organic framework nanoparticles (AuNPs/FeMOF)-modified glassy carbon electrode as an electrochemical sensor for the quantification of risperidone in patient plasma samples

Risperidone (RIS) is one of the most prescribed atypical antipsychotics approved for the treatment of various neuropsychiatric diseases. For the correlation of serum concentration and pharmacological effects of RIS, therapeutic drug monitoring is considered a fundamental concept for clinical application. This paper is provided to develop an electrochemical probe for the determination of RIS in biological samples by modification of glassy carbon electrode (GCE) using gold nanoparticles (AuNPs) and iron metal-organic-frameworks (FeMOFs). This probe fabrication process was characterized with various techniques including Fourier transform infrared (FTIR), emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), atomic force microscopy (AFM), and dynamic light scattering (DLS) to confirm the proper synthesis of materials and the sensors designing. The developed probe square-wave voltammetry (SWV) signal was linear upon RIS concentration from 0.02 to 50 µg/mL with a low limit of quantification (LOQ) of 0.02 µg/mL. Based on the validated method, high accuracy and precision, good specificity, and suitable stability of fabricated probes were achieved. As the ultimate step, this method was successfully applied for the quantification of RIS in patients' plasma samples with regular RIS consumption. The fabricated electrochemical demonstrates favorable clinical applicability due to its simplicity, high sensitivity, low sample pretreatment time, and rapid analysis time, making it a promising probe as an alternative to current separation-based methods. Also, the developed probe is cost-effective, as it uses a low amount of materials, decreases sample processing time, and utilizes inexpensive materials, which could remarkably reduce the overall cost of RIS concentration detection in clinical samples. The obtained results showed the potential of the developed probe for fast and reliable detection of RIS in plasma samples.

Spectrophotometric and smartphone-based colorimetric methods utilizing polyvinylpyrrolidone-capped silver nanoparticles for determining doxorubicin in human plasma samples

Doxorubicin (DOX) or adriamycin is a common anticancer drug with a narrow therapeutic index. Therefore, sensitive and reliable quantification of DOX is crucial for therapeutic drug monitoring purposes. In this study, both a spectrophotometric and a smartphone-based colorimetric method were fabricated to detect DOX in plasma samples. Both methods utilize polyvinylpyrrolidone (PVP)-capped silver nanoplates, which undergo color with varying DOX concentrations. The colorimetric method offers significant beneficial features of fast detection time, simplicity, and the ability to be easily observed by the naked eye without any need for expensive instruments. The linear dynamic ranges are 0.25-5.0 µg/mL and 0.5-5.0 µg/mL, with the lower limit of quantification (LLOQ) of 0.25 and 0.5 µg/mL for spectrophotometric and smartphone image analysis, respectively. The smartphone-based image analysis was performed using a smartphone application (PhotoMetrix), which relies on univariate calibration using the histograms of the RGB image. Using the smartphone camera, the image histograms were automatically generated and processed. The proposed probe can potentially be utilized to detect DOX in clinical samples with a mean accuracy and precision of 88.7% and 3.2%, respectively. The results demonstrated that these methods can accurately determine DOX concentrations in plasma samples, highlighting the potential of integrating digital imagery and smartphone applications with chemometric tools.

Electrochemistry as a Powerful Tool for Investigations of Antineoplastic Agents: A Comprehensive Review

Cancer is most frequently treated with antineoplastic agents (ANAs) that are hazardous to patients undergoing chemotherapy and the healthcare workers who handle ANAs in the course of their duties. All aspects related to hazardous oncological drugs illustrate that the monitoring of ANAs is essential to minimize the risks associated with these drugs. Among all analytical techniques used to test ANAs, electrochemistry holds an important position. This review, for the first time, comprehensively describes the progress done in electrochemistry of ANAs by means of a variety of bare or modified (bio)sensors over the last four decades (in the period of 1982-2021). Attention is paid not only to the development of electrochemical sensing protocols of ANAs in various biological, environmental, and pharmaceutical matrices but also to achievements of electrochemical techniques in the examination of the interactions of ANAs with deoxyribonucleic acid (DNA), carcinogenic cells, biomimetic membranes, peptides, and enzymes. Other aspects, including the enantiopurity studies, differentiation between single-stranded and double-stranded DNA without using any label or tag, studies on ANAs degradation, and their pharmacokinetics, by means of electrochemical techniques are also commented. Finally, concluding remarks that underline the existence of a significant niche for the basic electrochemical research that should be filled in the future are presented.

Polyrhodanine-based nanomaterials for biomedical applications: A review

Rhodanine is a heterocyclic organic compound that has been investigated for its potential biomedical applications, particularly in drug discovery. Rhodanine derivatives have been examined as the medication options for numerous illnesses, including cancer, inflammation, and infectious diseases. Some rhodanine derivatives have also shown promising activity against drug-resistant strains of bacteria and viruses. One of these derivatives is polyrhodanine (PR), a conducting polymer that has gained attention for its biomedical properties. This review article summarises the latest advancements in creating biomaterials based on PR for biosensing, antimicrobial treatments, and anticancer therapies. The distinctive characteristics of PR, such as biocompatibility, biodegradability, and good conductivity, render it an attractive candidate for these applications. The article also explores obstacles and potential future paths for advancing biomaterials made with PR, including synthesis modifications, characterisation techniques, and in vivo evaluation of biocompatibility and efficacy. Overall, as an emerging research topic, this review emphasises the potential of PR as a promising biomaterial for various biomedical applications and provides insights into the contemporary state of research and prospective directions for investigation.

2D MOF-enhanced SPR detector based on tunable supramolecular probes for direct and sensitive detection of DOX in serum

Therapeutic drug monitoring of doxorubicin (DOX) is important to study pharmacokinetics in patients undergoing chemotherapy for reduction of side effects and improve patient survival by rationally controlling the dose of DOX. A fast and ultra-sensitive surface plasmon resonance (SPR) detector without sample pre-handling was developed for DOX monitoring. First, the two-dimensional metal-organic framework was modified on the Au film to enhance SPR, and then, the supramolecular probes with tunable cavity structure were self-assembled at the sensing interface for direct detection of DOX through specific host-guest interactions with a low detection limit of 60.24 pM. The precise monitoring of DOX in serum proved the possibility of clinical application with recoveries in the range 102.86-109.47%. The mechanisms of host-guest interactions between supramolecular and small-molecule drugs were explored in depth through first-principles calculations combined with SPR experiments. The study paves the way for designing facile and sensitive detectors and provides theoretical support and a new methodology for the specific detection of small molecules through calixarene cavity modulation.

Electrochemical sensing of doxorubicin hydrochloride under sodium alginate antifouling conditions using silver nanoparticles modified glassy carbon electrodes

Doxorubicin (DOX) is a highly effective anticancer drug with a narrow therapeutic window; thus, sensitive and timely detection of DOX is crucial. Using electrodeposition of silver nanoparticles (AgNPs) and electropolymerization of alginate (Alg) layers on the surface of a glassy carbon electrode, a novel electrochemical probe was constructed (GCE). The fabricated AgNPs/poly-Alg-modified GCE probe was utilized for the quantification of DOX in unprocessed human plasma samples. For the electrodeposition of AgNPs and electropolymerization of alginate (Alg) layers on the surface of GCE, cyclic voltammetry (CV) was used in the potential ranges of -2.0 to 2.0 V and -0.6 to 0.2 V, respectively. The electrochemical activity of DOX exhibited two oxidation processes at the optimum pH value of 5.5 on the surface of the modified GCE. The DPV spectra of poly(Alg)/AgNPs modified GCE probe toward consecutive concentrations of DOX in plasma samples demonstrated wide dynamic ranges of 15 ng/mL-0.1 μg/mL and 0.1-5.0 μg/mL, with a low limit of quantification (LLOQ) of 15 ng/mL. The validation results indicated that the fabricated electrochemical probe might serve as a highly sensitive and selective assay for the quantification of DOX in patient samples. As an outstanding feature, the developed probe could detect DOX in unprocessed plasma samples and cell lysates without the requirement for pretreatment.

N-Doped Graphene Quantum Dots Confined within Silica Nanochannels for Enhanced Electrochemical Detection of Doxorubicin

Herein, we describe a fast and highly sensitive electrochemical sensor for doxorubicin (DOX) detection based on the indium tin oxide (ITO) modified with a binary material consisting of vertically-ordered mesoporous silica films (VMSFs) and N-doped graphene quantum dots (NGQDs). VMSFs, with high permeability and efficient molecular transport capacity, is attached to the ITO electrode via a rapid and controllable electrochemical method, which can serve as a solid template for the confinement of numerous NGQDs through facile electrophoresis. By virtue of the excellent charge transfer capacity, π-π and electrostatic preconcentration effects of NGQDs, as well as the electrostatic enrichment ability of VMSF, the presented NGQDs@VMSF/ITO shows amplified electrochemical signal towards DOX with a positive charge, resulting in good analytical performance in terms of a wide linear range (5 nM~0.1 μM and 0.1~1 μM), high sensitivity (30.4 μA μM-1), and a low limit of detection (0.5 nM). Moreover, due to the molecular sieving property of VMSF, the developed NGQDs@VMSF/ITO sensor has good selectivity and works well in human serum and urine samples, with recoveries of 97.0~109%, thus providing a simple and reliable method for the direct electrochemical analysis of DOX without complex sample pretreatment procedures.

A ratiometric electrochemical probe for the quantification of apixaban in unprocessed plasma samples using carbon aerogel/BFO modified glassy carbon electrodes

A novel electrochemical probe was established for the quantification of apixaban (APX) in unprocessed plasma samples. Efficiently oxidized graphene oxide aerogels (EEGO-AGs) and nano-sized Bi2Fe4O9 (BFO) particles were electrodeposited on the surface of a glassy carbon electrode (GCE). In this work, a ratiometric electrochemical method was introduced for APX detection to enhance the specificity of the probe in plasma samples. The fabricated ratiometric probe was employed for the indirect detection determination of APX using K3[Fe(CN)6]/K4[Fe(CN)6] as the redox pair. The differential pulse voltammetry technique was used to record the current alteration of the BFO/EEGO-AG-functionalized GCE probe at various APX concentrations. The probe response was proportional to the APX concentrations from 10 ng mL-1 to 10 μg mL-1 with a low limit of quantification (LLOQ) of 10 ng mL-1. After validation, this method was successfully utilized for the determination of APX in patients' plasma samples who have taken APX regularly. The fabricated chemosensor detected APX concentrations in unprocessed plasma samples with high selectivity, resulting from the physical filtering antifouling activity of aerogels.

Quantification of methotrexate in plasma samples using highly fluorescent nanoparticles

A novel amine-functionalized silica carbon polymer dots (APTES-CPDs)-based sensor was developed for methotrexate (MTX) detection. APTES-CPDs core-shell structure was synthesized via a one-step hydrothermal process and were employed as an optical sensor for MTX determination due to quenching effect of MTX on the fluorescence intensity of CPDs. Under optimum conditions, the developed sensor detects MTX in plasma samples in the dual linear ranges of 10 ng/mL to 2.0 µg/mL and 2.0 µg/mL to 50 μg/mL with a low limit of detections (LLOD)) of 10 ng/mL and 2.0 µg/mL, respectively. The obtained results are demonstrated the accuracy of the designed nanoprobe which is as high as to be used for the MTX detection in the routine therapeutic drug monitoring. In addition, the established nanoprobe shows significant specificity towards MTX compared to the co-administered drugs. Other advantages of this nanoprobe are its simple approach, high selectivity and sensitivity for MTX determination in plasma media which can approve the applicability of this MTX nanosensor in real samples.

Deep eutectic solvent synthesis of iron vanadate-decorated sulfur-doped carbon nanofiber nanocomposite: electrochemical sensing tool for doxorubicin

Detection of anticancer drug (doxorubicin) using an electrochemical sensor is developed based on a transition metal vanadate's related carbon composite material. With an environmentally friendly process, we have synthesized a metal oxide composite of iron vanadate nanoparticle assembled with sulfur-doped carbon nanofiber (FeV/SCNF). The FeV/SCNF composite was characterized using XRD, TEM, FESEM with elemental mapping, XPS and EDS. In contrast to other electrodes reported in the literature, a much-improved electrochemical efficiency is shown by FeV/SCNF composite modified electrodes. Amperometric technique has been employed at 0.25 V (vs. Ag/AgCl) for the sensitive detection of DOX within a wide range of 20 nM-542.5 μM and it possesses enhanced selectivity in presence of common interferents. The modified electrochemical sensors show high sensitivity of 46.041 μA μM^-1 cm^-2. The newly developed sensor could be used for the determination of doxorubicin in both blood serum and drug formulations with acceptable results, suggesting its feasibility for real-time applications.

Rapid and sensitive determination of doxorubicin in human whole blood by vertically-ordered mesoporous silica film modified electrochemically pretreated glassy carbon electrodes

Direct and accurate detection of doxorubicin (DOX) in unprocessed human whole blood is of vital importance in medical diagnosis and monitoring. In this work, we demonstrate the utilization of electrochemically pretreated glassy carbon electrodes (p-GCE) modified with vertically-ordered mesoporous silica films (VMSF) for rapid and sensitive electrochemical detection of DOX. The electrochemically pretreated process is a simple, cost-effective and environmentally friendly approach for improving interface catalytic properties and introducing oxygen-containing groups into the GCE surface, which could be suitable for stably growing VMSF without any adhesive layer simultaneously retaining the underlying electrode activity. Benefiting from the highly sensitive electrode substrate of p-GCE and electrostatic preconcentration effect of VMSF, the present VMSF/p-GCE sensor was able to determine DOX with an ultrahigh sensitivity (23.94 μA μM^-1) and a relatively low limit of detection (0.2 nM) and a rather wide linear range (0.5 nM to 23 μM). Furthermore, direct and reliable electrochemical detection of DOX in human whole blood without complicated sample pretreatments was achieved owing to the excellent anti-fouling and anti-interference ability of VMSF.

Applications of advanced materials in bio-sensing in live cells: Methods and applications

A wide variety of species, such as different ions, reactive oxygen species, and biomolecules play critical roles in many cell functions. These species are responsible for a range of cellular functions such as signaling, and disturbed levels could be involved in many diseases, such as diabetes, cancer, neurodegeneration etc. Thus, sensitive and specific detection methods for these biomarkers could be helpful for early disease detection and mechanistic investigations. New ultrasensitive sensors for detection of markers within living cells are a growing field of research. The present review provides updates in live cell-based biosensing, which have been published within the last decade. These sensors are mainly based on carbon, gold and other metals, and their physicochemical advantages and limitations are discussed. Advanced materials can be incorporated into probes for the detection of various analytes in living cells. The sensitivity is strongly influenced by the intrinsic properties of the nanomaterials as well their shape and size. The mechanisms of action and future challenges in the developments of new methods for live cell based biosensing are discussed.

Sensitive monitoring of doxorubicin in plasma of patients, MDA-MB-231 and 4T1 cell lysates using electroanalysis method

In the present work, an innovative electrochemical sensor was fabricated based on poly toluidine blue modified glassy carbon electrode (PTB-GCE). So, PTB-GCE was used for the detection and determination of doxorubicin hydrochloride (DOX) in cell lysate, and whole human plasma samples. PTB could enhance the rate of electrochemical reaction for the electro oxidation and detection of DOX in real samples. Cyclic voltammetry (CV) technique was used for the electro polymerization of toluidine blue on the surface of GCE with the applied potential ranging from -0.6 to 0.2 V. The sensor construction steps were approved by field emission scanning electron microscopy (FE-SEM), Energy dispersive X-ray spectroscopy (EDX) and electrochemical methods. Also, CV results indicated that the DOX is oxidized via two electrons and two protons process at the optimum pH of 6.5 using PTB modified GCE. Under optimized conditions, differential pulse voltammetry (DPV) technique response exhibited linear relationship between the oxidative peak current and concentration of DOX in the range of 17 nM - 8.6 μM with low limit of quantification (LLOQ) of 17 nM for untreated and treated human plasma samples. Also, determination of DOX in MDA-MB-231 and 4T1cell lysates were performed based on its direct electrochemical oxidation on PTB-GCE. Finally, analytical validation of DOX in human bio-fluids using FDA guideline were done successfully. Results suggested that the proposed electrochemical sensor can be used to the sensitive and selective determination of DOX in biological samples. The interaction results of DOX with cancer cells indicate the developed probe can easily detect candidate drug in cancer cells with high accuracy. To the best of our knowledge this is the first report of the determination of DOX based on the direct electrochemical oxidation on PTB-GCE and determination in MDA-MB-231 and 4T1 cell lysates. It is anticipated that this research open new horizons on the design of new class of electrochemical sensors for determination drugs, and therapeutic drug monitoring (TDM) in human bio-fluids.

Construction of a sensitive electrochemical sensor based on 1T-MoS2 nanosheets decorated with shape-controlled gold nanostructures for the voltammetric determination of doxorubicin

An innovative and portable design to fabricate an electrochemical sensor based on metallic phase MoS₂ (1T-MoS₂) decorated with shape-dependent gold nanostructures for the determination of doxorubicin (DOX) is presented. In this context, homogenous and uniform single-crystal gold nanospheres (AuNSPs) and nanorods (AuNRDs) were firstly synthesized by seeded growth approach. Afterwards, AuNSPs and AuNRDs were anchored on 1T-MoS₂ surfaces to construct the desired electrochemical sensing platform towards the DOX assay. 1T-MoS₂ was exfoliated by metal intercalation process using NaK metal alloys. The structure and surface morphology of 1T-MoS₂, AuNSPs, and AuNRDs were characterized by XPS, Raman, UV-vis, TEM, and SEM. The electrochemical behavior of DOX using various MoS₂-based electrochemical sensors prepared on screen-printed electrode (SPE) was examined by cyclic voltammetry and adsorptive stripping differential pulse voltammetry. The electrocatalytic efficiency of AuNRDs on 1T-MoS₂ was also compared with that of AuNSPs on 1T-MoS₂, and it showed much better electrocatalytic activity towards the DOX. A nanocomposite prepared with AuNRDs and 1T-MoS₂ on SPE (AuNRDs/1T-MoS₂/SPE) exhibited a linear relationship between peak current and DOX concentration in the range 0.01-9.5 μM with a detection limit of 2.5 nM. The AuNRDs/1T-MoS₂/SPE was successfully applied to the sensitive and rapid determination of DOX in spiked human serum samples with satisfactory recoveries in the range 99.2-100.8%. Graphical abstract Schematic representation of a portable design for electrochemical sensor based on shape-controlled gold nanostructures decorated on metallic phase molybdenum disulfide (1T-MoS₂) towards the sensitive determination of doxorubicin.

A Novel Sensitive Doxorubicin Hydrochloride Electrochemical Sensor Based on a Nickel Hexacyanoferrate/Ni-Al-LDH Modified Gold Electrode

A highly sensitive and selective electrochemical sensor has been fabricated by the electrodepositing of nickel hexacyanoferrate (NiHCF) on a Ni-Al layered double hydroxides (Ni-Al-LDH) modified Au electrode for the quantification of doxorubicin hydrochloride (DOX). The characterization of synthesized nanomaterials has been conducted by scanning electron microscopy, energy dispersive X-ray spectroscopy and electrochemical methods. The synergistic effect of NiHCF and Ni-Al-LDH not only excellently improves the performance of DOX electro-reduction, but also promotes electron transfer between DOX and the NiHCF/Ni-Al-LDH/Au sensor. The differential pulse voltammetric response of the NiHCF/Ni-Al-LDH/Au sensor shows a linear relationship with the concentration of DOX in the range of 1.0 × 10-8 - 6.2 × 10-6 mol L-1, a limit of detection of 1.9 × 10-9 mol L-1 (S/N = 3) and a sensibility of 14.71 A mol L-1 cm-2. The developed sensor exhibits good sensitivity, reproducibility, anti-interference and a long-term stability property. Furthermore, the NiHCF/Ni-Al-LDH/Au sensor has been successfully applied to determine DOX in biological samples and human blood serum samples.

Electrochemical Sensor Based on Poly(Azure B)-DNA Composite for Doxorubicin Determination

A new voltammetric DNA sensor has been developed for doxorubicin determination on the platform of a glassy carbon electrode (GCE) covered with electropolymerized Azure B film and physically adsorbed native DNA. The redox properties of polymeric Azure B were monitored at various pH and scan rates. DNA application decreased the peak currents related to polymeric and monomeric forms of the dye, whereas incubation in doxorubicin solution partially restored the peaks in accordance with the drug and DNA concentration. The relative shift of the cathodic peak current caused by doxorubicin depended on the nominal DNA concentration and its application mode. In optimal conditions, the DNA sensor makes it possible to determine between 0.1 μM to 0.1 nM doxorubicin (limit of detection 7×10-11 M). The DNA sensor was tested on commercial doxorubicin formulations and on artificial samples the mimicked electrolyte content of human serum.

Non-enzymatic Determination of L-Proline Amino Acid in Unprocessed Human Plasma Sample Using Hybrid of Graphene Quantum Dots Decorated with Gold Nanoparticles and Poly Cysteine: A Novel Signal Amplification Strategy

An innovative electrochemical interface for quantitation of L-proline (L-Pro) based on ternary amplification strategy was fabricated. In this work, gold nanoparticles prepared by soft template methodology were immobilized onto green and biocompatible nanocomposite containing poly as a conductive matrix and graphene quantum dots as the amplification element. Therefore, a novel multilayer film based on poly-L-cysteine, graphene quantum dots (GQDs), and gold nanoparticles (GNPs) was exploited to develop a highly sensitive electrochemical sensor for the detection of L-Pro. Fully electrochemical methodology was used to prepare a new transducer on a glassy carbon electrode, which provided a high surface area towards sensitive detection of L-Pro. The prepared electrode was employed for the detection of L-Pro. Under optimized conditions, the calibration curve for L-Pro concentration was linear in 0.5 nM - 10 mM with a low limit of quantification of 0.1 nM. The practical analytical utility of the modified electrode was illustrated by determination of L-Pro in unprocessed human plasma samples.

An innovative immunosensor for detection of tumor suppressor protein p53 in unprocessed human plasma and cancer cell lysates

An innovative mediator-free electrochemical immunosensor for quantitation of p53 tumor suppressor protein based on signal amplification strategy was fabricated. In this work, biotin conjugated p53-antibody (anti-p53) was immobilized onto a green and biocompatible nanocomposite containing poly l-cysteine (P-Cys) as conductive matrix and 3D gold nanoparticles (GNPs) as signal amplification element. Therefore, a novel nanocomposite film based on P-Cys and GNPs was exploited to develop a highly sensitive immunosensor for detection of p53 protein. Importantly, GNPs prepared by sonoelectrodeposition method which lead to compact morphology. Fully electrochemical methodology was used to prepare a new transducer on a gold surface which provided a high surface area to immobilize a high amount of the anti-p53. The surface morphology of electrode was characterized by high-resolution field emission scanning electron microscope (FE-SEM) and energy dispersive spectroscopy (EDX). The immunosensor was employed for the detection of p53 in physiological pH using square wav voltammetry and differential pulse voltammetry (DPVs) techniques. Under optimized condition the calibration curve for p53 concentration by SWV and DPV was linear in 0.0369-50pM and 0.018-2.5pM with lower limit of quantification of 48fM and 18fM, respectively. The method was successfully applied assay of the p53 in unprocessed human plasma samples. Also, the method was applied to the assay of p53 in human plasma sample and normal and malignant cell line lysates such as (L929 normal cell Line from mouse C3H (L929), colon cancer cell-HCT, prostate cancer cell line PC-3, and human breast adenocarcinoma cell line-MCF7).