Browsing by Author "Pinky Sagar"

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A contemporary overview on quantum dots-based fluorescent biosensors: Exploring synthesis techniques, sensing mechanism and applications
(Elsevier B.V., 2025) Anushka Yadav; Priyanka Dogra; Pinky Sagar; Monika Srivastava; Amit Kumar Srivastava; Rajneesh Kumar; Sanjay Kumar Srivastava
In the epoch of bioinformatics, pivotal biomedical scrutiny and clinical diagnosis hinge upon the unfolding of highly efficacious biosensors for intricate and targeted identification of specific biomolecules. In pursuit of developing robust biosensors endowed with superior sensitivity, precise selectivity, rapid performance, and operational simplicity, semiconductor QDs have been acknowledged as pivotal and advantageous entities. In this review, we present a comprehensive analysis of the latest unfolding within the domain of QDs used in fluorescent biosensors for the detection of diverse biomolecular entities, encompassing proteins, nucleic acids, and a range of small molecules, with an emphasis on the synthesis methodologies of QDs employed and mechanism behind sensing. Additionally, this review delves into several pivotal facets of QD-based fluorescent biosensors in detail, such as surface functionalization methodologies aimed at enhancing biocompatibility and improving target specificity. The challenges and future perspectives of QD-based fluorescent biosensors are also considered, emphasizing the necessity of ongoing multidisciplinary research to realize their full potential in enhancing personalized medicine and biomedical diagnostics. © 2025 Elsevier B.V.
A dual epitope-imprinted polymer@AuNP-MoS2 nanosheets-EQCM sensor for antibody free detection of SipD protein of Salmonella typhi bacteria with high selectivity
(Elsevier B.V., 2025) Akriti Srivastava; Ashish Kumar Kushwaha; Pinky Sagar; Anirban Parida; Roop Shikha Singh; Sanjay Kumar Srivastava; Richa Raghuwanshi; Gopal Nath; Meenakshi K. Singh
Dual-epitope imprinted EQCM sensor for selective and sensitive detection of Salmonella typhi bacterial protein is fabricated on gold nanoparticle decorated MoS2 nanosheets (AuNPs-MoS2NSs). Salmonella invasive protein D (SipD) binds to the needle protein and appears capable of interacting with the translocon complex to infect the host. Potential B cell antigenic epitope sequences from bacterial tip protein, SipD were intentionally tagged with cysteine and are used as dual templates to fabricate MIP sensor using methacryloyloxyethyl phosphorylcholine (MPC), benzyl methacrylate (BMA) and methacrylic acid (MAA) as monomers and N , N ′-methylene- bis -acrylamide as a crosslinker. The monomers chosen through docking produced a DEIP-EQCM sensor. The sensor was able to show specific binding towards the blood samples of infected patients, even in the presence of ‘matrix’ of ‘real’ samples and other plasma proteins. It has shown excellent specificity, sensitivity and selectivity in sensing range of 100–1000 nM with detection limit 1.65 nM (Epitope I) and 0.025 nM (Epitope II) and limit of quantification as 5.03 nM (Epitope I) and 0.075 nM (Epitope II) for the two epitope sequences imprinted. Sip D protein binding was substantiated by SDS-PAGE analysis. The repetitive experimental runs could not mutilate the specific geometries of respective imprinted cavities and the DEIP-EQCM sensor can be proposed for antibody free detection of Sip D protein. © 2025 The Authors.
A sensitive SPR biosensor for glucose detection using MoS2 quantum dots
(Elsevier Inc., 2025) Awadhesh Kumar; A. Sameer Ruban Kumar; Pinky Sagar; Monika Srivastava; Amritanshu Pandey; Rajiv Prakash; Sanjay Kumar Srivastava
Diabetes patients require continuous blood glucose monitoring throughout the year. In this study, we present a highly sensitive surface plasmon resonance (SPR) biosensor for glucose detection, utilizing molybdenum disulfide quantum dots (MoS2 QDs). The proposed biosensor is based on the Kretschmann configuration, consisting of sequentially deposited layers of chromium (Cr), gold (Au), L-cysteine (Cys), and MoS2 QDs on a BK-7 glass substrate through a coating technique. A self-assembled monolayer (SAMs) of Cys is employed to covalently bond the amine groups to the Au surface, ensuring strong adhesion. The sensor demonstrates a linear detection range of 0.5–10 mM for glucose, with a limit of detection (LOD) of 0.31 mM. The experimental results align well with theoretical predictions calculated using the transfer matrix method, indicating strong agreement between the two. Additionally, the biosensor exhibits excellent selectivity in the presence of other biomolecules, specifically showing a high affinity for glucose. The proposed SPR biosensor is highly promising for blood D-glucose detection in diabetic patients due to its miniaturization, high sensitivity, and stability. This work highlights its potential for application in real-time glucose monitoring devices. © 2025 Elsevier B.V.
A smartphone-enabled colorimetric sensor based on VS2 quantum dots for Rapid and on-site detection of ferric ions
(Elsevier B.V., 2025) Anushka Yadav; Pinky Sagar; Monika Srivastava; Amit Kumar Srivastava; Rajneesh Kumar; Sanjay Kumar Srivastava
This research delves into the holistic hydrothermal synthesis of VS2 QDs and their subsequent utilization as a fluorescent probe for the subtle detection of ferric ions (Fe3+) in practical sample matrices. The detection paradigms harness a colorimetric sensing mechanism, amplified by smartphone-enabled analytical integration for improved precision and real-time monitoring. A comprehensive suite of analytical characterization techniques has been employed, revealing that the as-synthesized VS2 QDs feature a surface densely populated with functional groups. While the VS2 QDs showcase interactions with multifarious metal ions in aqueous media, they set forth a pronounced and selective fluorescent quenching response toward Fe3+ ions, markedly surpassing their interactions with other metal ions. The developed sensing probe exhibits a linear detection range spanning from 0 – 90 μM, with a LOD as low as 2.25 μM, also exhibits exceptional sensitivity (KD ∼ 0.8 × 104 M−1) and remarkable selectivity for Fe3+ ions, harnessing the intrinsic photoluminescent characteristics of VS2 QDs. In addition, a sophisticated portable smartphone platform, integrated with a radiometric fluorescence probe specifically tailored for in-situ detection of Fe3+ at the point of care, exhibits a LOD of approximately 5.05 μM, a value that resides below the prescribed safety threshold. Thus, the proposed probe stands to function as an exceptionally potent sensing apparatus for the precise quantification of Fe3+ in complex real-world samples. © 2024 Elsevier B.V.
Boron functionalized and phosphorous doped molybdenum di-sulfide quantum dots for the photoluminescence based detection of HbA1c
(Elsevier Inc., 2024) Pinky Sagar; Monika Srivastava; S.K. Srivastava
Highly fluorescent transition metal dichalcogenides (TMDs) based quantum dots (QDs) have been the focus of immense research owing to their bio-compatibility, non-toxicity, easy chemical synthesis and broad spectrum of applications which includes biosensing, optoelectronics, energy storage devices, etc. Herein, we present a one-step hydrothermal growth of in-situ blue fluorescent phosphorous doped-molybdenum di sulfide QDs (P-MoS2 QDs) in aqueous media. A range of functional groups over the surface of chemically synthesized P-MoS2 QDs helps in conserving its fluorescence along with high aqueous stability and solubility. Besides, remarkable photoluminescence (PL) properties of P-MoS2 QDs were then explored to concoct an optical sensor with excellent selectivity and sensitivity for glycated hemoglobin (HbA1c) followed by functionalization with boronic acid. The response of the sensor was found to be linear in the range of 2–15 %, which is under the typical physiological aliquot range (0.75–22.93 mM with limit of detection to be 77.5 μM, under optimized conditions. Moreover, PL quenching processes and TRPL data of P-MoS2 QDs were explored to elucidate the plausible quenching mechanism which suggests mixed kind of quenching processes. In conclusion, we envisaged that the present methodology can provide an effective and potent tool for HbA1c sensing in real biological (hemolysate/whole blood-lysate) samples. © 2024 Elsevier B.V.
Electrochemical Sensor for the Anti-tuberculosis Drug Rifampicin on CuO@rGO-Nanocomposite-Modified GCE by Voltammetry Techniques
(John Wiley and Sons Inc, 2022) Pinky Sagar; Monika Srivastava; Sanjay K. Srivastava
Reduced-graphene-oxide layers (rGO) offer extremely subtle transducer thin-films and can be unified in interdigital micro-electrodes for various purposes. Understanding the functions and nature of rGO specially bio-compatibility, we can use this as potent-tool for the detection of antibiotic-drug Rifampicin (RFP) in standard/pharmaceutical samples. Herein, we synthesize CuO@rGO nano-composite and explored its potency for the preparation of electrochemically-active-electrodes. Catalytic-activity of as-synthesized CuO@rGO nano-composite is checked in 1.0 mM of Fe2+/3+ solutions and found to be more than three times higher current as compared to bare, rGO or CuO modified GCE. Subsequently, modified electrodes are used to detect RFP via two-techniques (differential-pulse voltammetry viz. DPV and cyclic-voltammetry viz. CV) in three-ways simultaneously. The CuO@rGO-modified-GCE (CuO@rGO/GCE) exhibits remarkable sensitivity with very low-detection-limit of 5–11 nM and long term-usage, which is far-better than other reported works. Non-interfering ability in existence of several body-interferents exposes that CuO@rGO/GCE could be an effective/ beneficial contrivance for the detection of RFP. © 2022 Wiley-VCH GmbH.
Excellent supercapacitive performance of graphene quantum dots derived from a bio-waste marigold flower (Tagetes erecta)
(Elsevier Ltd, 2021) Gopal Krishna Gupta; Pinky Sagar; Monika Srivastava; Ashwani Kumar Singh; Jai Singh; S.K. Srivastava; Amit Srivastava
Marigold flower (MG; Tagetes erecta) derived Graphene quantum dots (GQDs) have been successfully reported for the fabrication of supercapacitor electrodes in charge storage devices. The GQDs have been synthesized through a hydrothermal route using biomass viz. Waste material (MG) without adding any hazardous chemicals. The successful formation of GQDs as elaborated has been confirmed by various analytical characterization techniques. The as-synthesized GQDs have been electrodeposited on the Ni foil (working electrode) with the help of PVDF (binder) and subsequently, cyclic voltammetry (CV) has been conducted to access specific capacitance, energy density, and other parameters. Moreover, the galvanometric charge/discharge (GCD) technique has been employed due to its accuracy and reliability. Maximum areal specific capacitance has been found as 1.6008 F/cm2 with the current density of 2.0 A/g even after loading a little amount of material on the electrode. The high magnitude of columbic efficiency (160.08), energy density (17.78 Wh/kg), and specific capacitance of 200 F/g at current density 2.0 A/g within a voltage range of −0.55 V to +0.25 V in 2 M KOH electrolyte solution indicate a good electrocapacitive performance of the as-synthesized material. Moreover, the as-synthesized GQDs have shown excellent capacitive retention after 1000th cycles which clearly embarks its sustainable electrocapacitive nature and henceforth offers outstanding potential for the applications in energy storage devices like supercapacitors. © 2021
Hydrothermally synthesized nickel ferrite nanoparticles integrated reduced graphene oxide nanosheets as an electrode material for supercapacitors
(Springer, 2024) Gopal Krishna Gupta; Pinky Sagar; Monika Srivastava; Ashwani Kumar Singh; Jai Singh; S.K. Srivastava; Amit Srivastava
In the present study, we have employed an integrative strategy to synthesize a three-dimensional hierarchical electrode material consisting of NiFe2O4/r-GO nanostructures using a simple hydrothermal process and subsequently explored its electrocapacitive performance. The structural and morphological characteristics of the as-synthesized NiFe2O4/r-GO nanostructure have been accessed through X-ray diffraction (XRD), Raman spectroscopy, Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), and X-ray photospectrometer (XPS). The electrocapacitive performances of the as-synthesized sample have been evaluated by galvanostatic charge–discharge (GCD), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) using a three-electrode system with 3-M KOH electrolyte solution. As-prepared hierarchical electrode material exhibits specific capacity ∼ 362.46 F g−1 at a current density of 0.65 A g−1, suggesting good rate capability. Furthermore, NiFe2O4/r-GO-nanostructured electrode material displays a significant high energy ∼ 36.37 Wh/kg and power density as ∼ 276.22 W/kg. Moreover, the as-synthesized nanocomposite harvests a superior cycling stability over 5000 cycles without obvious capacitance attenuation. The NiFe2O4/r-GO provides rapid pathways for electron transfer and diminishes the ion diffusion routes due to NiFe2O4 over r-GO sheets, which ultimately results in exceptional electrochemical properties. Henceforth, NiFe2O4/r-GO nanocomposite which renders a new reasonable design to manifest more energy density and deliver maximum power may be enrooted as a promising/prospective electrode material due to its unique morphological properties, superior conductivity, and favorable cyclic stability in the field of energy storage applications. © 2024, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
In Situ Fabrication of Activated Carbon from a Bio-Waste Desmostachya bipinnata for the Improved Supercapacitor Performance
(Springer, 2021) Gopal Krishna Gupta; Pinky Sagar; Sumit Kumar Pandey; Monika Srivastava; A.K. Singh; Jai Singh; Anchal Srivastava; S.K. Srivastava; Amit Srivastava
Herein, we demonstrate the fabrication of highly capacitive activated carbon (AC) using a bio-waste Kusha grass (Desmostachya bipinnata), by employing a chemical process followed by activation through KOH. The as-synthesized few-layered activated carbon has been confirmed through X-ray powder diffraction, transmission electron microscopy, and Raman spectroscopy techniques. The chemical environment of the as-prepared sample has been accessed through FTIR and UV–visible spectroscopy. The surface area and porosity of the as-synthesized material have been accessed through the Brunauer–Emmett–Teller method. All the electrochemical measurements have been performed through cyclic voltammetry and galvanometric charging/discharging (GCD) method, but primarily, we focus on GCD due to the accuracy of the technique. Moreover, the as-synthesized AC material shows a maximum specific capacitance as 218 F g−1 in the potential window ranging from − 0.35 to + 0.45 V. Also, the AC exhibits an excellent energy density of ~ 19.3 Wh kg−1 and power density of ~ 277.92 W kg−1, respectively, in the same operating potential window. It has also shown very good capacitance retention capability even after 5000th cycles. The fabricated supercapacitor shows a good energy density and power density, respectively, and good retention in capacitance at remarkably higher charging/discharging rates with excellent cycling stability. Henceforth, bio-waste Kusha grass-derived activated carbon (DP-AC) shows good promise and can be applied in supercapacitor applications due to its outstanding electrochemical properties. Herein, we envision that our results illustrate a simple and innovative approach to synthesize a bio-waste Kusha grass-derived activated carbon (DP-AC) as an emerging supercapacitor electrode material and widen its practical application in electrochemical energy storage fields. © 2021, The Author(s).
In-situ One-Pot Novel Synthesis of Molybdenum di-Telluride@Carbon Nano-Dots for Sensitive and Selective Detection of Hydrogen Peroxide Molecules via Turn-off Fluorescence Mechanism
(Elsevier Inc., 2022) Pinky Sagar; Monika Srivastava; Rajan Kumar Tiwari; Ajay Kumar; Amit Srivastava; Gajanan Pandey; S.K. Srivastava
Transition metal dichalcogenides (TMDs) based materials have grabbed striking attention to a great extent owing to their intriguing characteristics for biological, optical, chemical and medicinal applications. Herein, we report in-situ one-pot hydrothermal-synthesis of molybdenum ditelluride@carbon nano-dots (MoTe2@C NDs) and then explored its potency in biosensing. The MoTe2@C NDs have been characterized by using X-ray Photoelectron Spectroscopy (XPS), Raman spectroscopy and Transmission Electron Microscopy (TEM) for confirmation. Furthermore, the photophysical properties of MoTe2@C NDs have been examined. Under radiation of Ultra-Violet (UV) light (λ = 365 nm), the MoTe2@C NDs emit cyan fluorescence which has been confirmed by photoluminescence (PL) spectroscopy (PL peak at ∼431 nm, excitation wavelength ∼350 nm). The as-synthesized sample has been subjugated for the sensing of hydrogen-peroxide (H2O2) molecules. Notably, with a gradual proliferation of the concentration of H2O2, the PL intensity of the MoTe2@C NDs decreases and is found to be linear (R2 = 0.9986). The detection-limit has also been estimated as 14.22 nM. The PL quenching-mechanism has been elucidated based on three-level kinetic model considering charge separated-trap states (1[D+···A−] ↔ 3[D+···A−]). This is the first work of hydrothermal-synthesis of MoTe2@C NDs and study of its optical properties, which has efficient potential to use as H2O2 sensor in industrial/biomedical applications. © 2022 Elsevier B.V.
Synthesis and characterization of graphene oxide-based nanofluids and study of their thermal conductivity
(Springer Science and Business Media B.V., 2022) Sachin Kumar Yadav; Diptarka Roy; Anil Kumar Yadav; Pinky Sagar; Sarvesh Kumar Avinashi
In the present research work, we investigated the effect of loading mass concentrations (0.05%, 0.15%, and 0.25 mass %) and temperature (10–50 °C) on the thermal properties of graphene oxide-ethylene glycol (GO-EG) nanofluids. A two-step approach was adopted to prepare the GO-EG nanofluids with different mass proportions without any surfactant. The thermal kinetic analysis was performed by modulated DSC and TGA. Thermal stability and particle size distribution of the nanofluids were monitored by using UV–visible spectroscopy and dynamic light scattering. The experimental findings on the thermal transport characteristics of the as-prepared nanofluid samples are influenced by loading mass concentration, increasing temperature because of the high relative area of dispersed nanoparticles at higher particle concentration, dispersion quality of nanofluids. The thermal conductivity (TC) of GO-EG nanofluid shows an enhancement of 36.72% for (sample no. 3, i.e., GO 3) and shows a semi-linear dependence profile between temperature and TC, with increasing mass concentration due to the decrease in interfacial thermal resistance between GO and EG. The observed results are in good agreement with previously reported literature and reveal the promising prospect for usage as a state-of-the-art heat transport fluid in the coolant industry. © 2022, Akadémiai Kiadó, Budapest, Hungary.
Tagetes erecta as an organic precursor: Synthesis of highly fluorescent CQDs for the micromolar tracing of ferric ions in human blood serum
(Royal Society of Chemistry, 2021) Pinky Sagar; Gopal Krishna Gupta; Monika Srivastava; Amit Srivastava; S.K. Srivastava
The present article illustrates the green synthesis of novel carbon quantum dots (CQDs) from biomass viz. Tagetes erecta (TE), and subsequently fabrication of a metal ion probe for the sensing of Fe3+ in real samples. TE-derived CQDs (TE-CQDs) have been synthesized by a facile, eco-friendly, bottom-up hydrothermal approach using TE as a carbon source. The successful synthesis and proper phase formation of the envisaged material has been confirmed by various characterization techniques (Raman, XRD, XPS, TEM, and EDS). Notably, the green synthesized TE-CQDs show biocompatibility, good solubility in aqueous media, and non-toxicity. The as-synthesized TE-CQDs show an intense photoluminescence peak at 425 nm and exhibit excitation dependent photoluminescence behavior. The proposed TE-CQD-based probe offers a remarkable fluorescence (FL) quenching for Fe3+ with high selectivity (Kq ∼ 10.022 × 1013 M-1 s-1) and a sensitive/rapid response in a linear concentration range 0-90 μM (regression coefficient R2 ∼ 0.99) for the detection of Fe3+. The limit of detection (LOD) of the probe for Fe3+ has been found as 0.37 μM in the standard solution. It has further been applied for the detection of Fe3+ in real samples (human blood serum) and displays good performance with LOD ∼ 0.36 μM. The proposed TE-CQD-based ion sensing probe has potential prospects to be used effectively in biological studies and clinical diagnosis. This journal is © The Royal Society of Chemistry.
The fabrication of an MoS2 QD-AuNP modified screen-printed electrode for the improved electrochemical detection of cefixime
(Royal Society of Chemistry, 2020) Pinky Sagar; Monika Srivastava; Rajiv Prakash; S.K. Srivastava
Herein, we report a voltammetric method for the nanomolar detection of cefixime, a third-generation antibiotic. The determination of cefixime is validated on a glassy carbon electrode (GCE) as well as on a screen-printed carbon electrode (SPCE). In the present study, we have reported a facile "one step simple hydrothermal synthesis" of MoS2 quantum dots and with the oxidation of aurochloric acid for the further formation of an MoS2 QD-AuNP composite. The as-synthesized nanocomposite was characterized via UV-Vis spectroscopy, FTIR spectroscopy, XRD, TEM and EDX techniques, and further applied in the modification of working electrodes, showing excellent electroactivity. The sensing of cefixime was done via cyclic and differential pulse voltammetry techniques. The presence of the only anodic peak in the voltammogram reveals the irreversible oxidation of cefixime in the potential range of about 1.3 ± 0.1 V vs. Ag/AgCl. The study was also performed at different scan rates, which indicate a diffusion-controlled mechanism. The proposed cefixime sensor showed a linear response in the concentration range of 0.33-90.82 μM (at S/N = 3) with a limit of detection (LOD) of 3.9-4.5 nm. The electrochemical sensitivity is calculated as 8.63 μA μM-1 cm-2 and 7.07 μA μM-1 cm-2 in buffer and pharmaceutical formulation (commercially available cefixime tablet), respectively. The effects of several interferents were also investigated. The proposed sensor is effectively used for estimating cefixime in phosphate buffer and the commercially available cefixime tablets with no cross-reactivity or matrix effects and shows a promising prospect for real applications. © 2020 The Royal Society of Chemistry.
Wireless & portable smartphone assisted electrochemical platform for on-site monitoring of chloramphenicol drug
(Elsevier Ltd, 2025) Priyanka Dogra; Monika Srivastava; Pinky Sagar; Chandra Shekhar Pati Tripathi; Sanjay Kumar Srivastava
Precise detection of antibiotic residues such as chloramphenicol (CAP) remains challenging due to their widespread use in veterinary, food, medical, and environmental sectors. Herein, we report a smartphone-assisted electrochemical sensor with graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) for the sensitive detection of CAP. The system integrates with both a traditional Autolab potentiostat and a pocket size Palmsens potentiostat. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) studies of GO@MWCNT nanocomposite exhibited excellent electrocatalytic activity, with a linear detection range of 0–600 μM, a limit of detection (LOD) of 46 nM (S/N = 3), and sensitivity of 1.71 μA μM−1 cm−2. The sensor showed excellent stability (∼90 % retention after 21 days) and reproducibility (RSD <3 %). A strong correlation between Autolab and smartphone-based results validated the reliability of the system. This is the first report of a smartphone-assisted platform for CAP detection, enabling wireless, Bluetooth enabled, and real-time analysis via a user-friendly smart phone application. The sensor performed effectively in milk, tap water, eye drops, capsules, and human blood serum, with good recoveries. A reusability/regeneration study confirmed the potential of the platform as a cost-effective, field-deployable POC diagnostic tool. © 2025 Elsevier B.V.
WS2 nanoparticle integrated MWCNT as an efficient electrode material for electrochemical sensing of chloramphenicol in pharmaceutical samples
(Elsevier Inc., 2025) Pinky Sagar; Ayushi Sahrawat; Monika Srivastava; Priyanka; Pooja Agarwal; Sanjay Kumar Srivastava
Detection of an antibiotic drug chloramphenicol (CPN) in pharmaceutical samples is very essential due to its wide application in food, agriculture and healthcare sector and nanomaterials are gaining significant attention as efficient electrode materials in the realm of CPN residue diagnostics. Among these materials, graphene-based compounds stand out due to their intriguing π–π interaction properties. In this study, we present a facile hydrothermal technique for the synthesis of WS2 nanoparticles which later decorated on multiwalled carbon nanotubes (WS2-MWCNT). This nanocomposite material was then employed for the electrochemical detection of CPN simultaneously by two techniques: cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The WS2-MWCNT based sensor exhibited an impressive low limit of detection of 0.041 nM (CV) and 0.34 nM (DPV), and a remarkable sensitivity of 4.29 μAμM−1cm−2 (CV) and 0.71 μAμM−1cm−2 (DPV), along with excellent performance in terms of selectivity, and reproducibility for CPN detection. Furthermore, the sensor demonstrated successful detection of CPN in pharmaceutical and natural matrices with satisfactory results. This proposed voltammetric sensor presents an inexpensive and promising approach for applications in monitoring pharmaceutical samples, with great opportunities for its miniaturization and detection in real samples. © 2025 Elsevier B.V.