Electrode Surface Research Articles

Buffering Donor Shuttles in Proton-Coupled Electron Transfer Kinetics for Electrochemical Hydrogenation of Hydroxyacetone to Propylene Glycol.

Electrochemical hydrogenation reactions demand rapid proton-coupled electron transfer at the electrode surface, the kinetics of which depend closely on pH. Buffer electrolytes are extensively employed to regulate pH over a wide range. However, the specific role of buffer species should be taken into account when interpreting the intrinsic pH dependence, which is easily overlooked in the current research. Herein, we report the electrochemical hydrogenation of hydroxyacetone, derived from glycerol feedstock, to propylene glycol with a faradaic efficiency of 56 ± 5% on a polycrystalline Cu electrode. The reaction activities are comparable in citrate, phosphate, and borate buffer electrolytes, encompassing different buffer identities and pH. The electrokinetic profile reveals that citrate is a site-blocking adsorbate on the Cu surface, thereby decreasing buffer concentration and increasing pH will enhance the reaction rate; phosphate is an explicit proton donor, which promotes the interfacial rate by increasing buffer concentration and decreasing pH, while borate is an innocent buffer, which can be used to investigate the intrinsic pH effect. Combined with in situ SEIRAS, we demonstrate that water is the primary proton source in citrate and borate electrolytes, reiterating the rationality of the proposed mechanism based on the microkinetic modeling. Our results emphasize the intrinsic complexity of the buffer system on the kinetic activity for electrocatalysis. It calls for special care when we diagnose the mechanistic pathway in buffer electrolytes convoluted by different buffer identities and pH.

Control of Ag deposition for improvement of specular reflection in Ag deposition-based electrochemical mirror through modulation of electrolysis condition

The reflection behavior of an Ag deposition-based reversible electrochemical mirror is determined by the morphology of the electrodeposited Ag. This study demonstrates the control of the morphology of Ag deposits through the modulation of the electrolysis conditions, specifically the applied potential and Ag+ ions concentration, without increasing the amount of Ag deposits. By applying a potential with a sufficiently large deposition overpotential for continuous deposition on the electrode surface, the deposited Ag formed a flat surface, resulting in high reflectivity. Considering the concentration dependence of Ag+ ions, the diffusion of Ag+ ions to the electrode significantly affected the resulting morphology of the deposits. At higher Ag+ concentrations, the time for the transition to a diffusion-limited process increased because Ag+ ions were close to the working electrode. Therefore, a flat Ag layer was obtained due to the promotion of three-dimensional deposition, including the in-plane growth.

Colloid Electrolyte Containing Li3P Nanoparticles for Highly Stable 4.7 V Lithium Metal Batteries.

Lithium metal batteries (LMBs) with LiNi0.8Co0.1Mn0.1O2 (NCM811) cathodes have garnered significant interest as next-generation energy storage devices due to their high energy density. However, the instability of their electrode/electrolyte interfaces in regular carbonate electrolytes (RCEs) results in a rapid capacity decay. To address this, a colloid electrolyte consisting of Li3P nanoparticles uniformly dispersed in the RCE is developed by a one-step synthesis. This design concurrently creates stable cathode electrolyte interphase (CEI) and solid electrolyte interphase (SEI) on both electrode surfaces. The cathode interface derived from this colloid electrolyte significantly facilitates the decomposition of Li salts (LiPF6 and LiDFOB) on the cathode surface by weakening the P-F and B-F bonds. This in situ formed P/LiF-rich CEI effectively protects the NCM811 cathode from side reactions. Furthermore, the Li3P embedded in the SEI optimizes and homogenizes the Li-ion transport, enabling dendrite-free Li deposition. Compared to the RCE, the designed colloid electrolyte enables robust cathode and anode interfaces in NCM811||Li full cells, minimizing gas and dendrite formation, and delivering a superior capacity retention of 82% over 120 cycles at a 4.7 V cutoff voltage. This approach offers different insights into electrolyte regulation and explores alternative electrolyte shapes and formulations.

Revealing the Role of Mo Leaching in the Structural Transformation of NiMo Thin Film Catalysts upon Hydrogen Evolution Reaction.

NiMo alloys are considered highly promising non-noble Hydrogen Evolution Reaction (HER) catalysts. Besides the synergistic effect of alloying elements, recent attention is drawn to the Mo leaching from the catalyst. This work investigates the role of Mo in NiMo alloys during HER, aiming to understand the interplay between compositional, structural, and electronic factors on the activity, and their effects on the electrode material and catalyst properties. For this purpose, sputter-deposited low roughness NixMo100-x thin films are produced. The investigation of catalyst performance depending on their chemical composition shows a volcano-shaped plot, peaking for the Ni65Mo35 alloy with the highest intrinsic activity in alkaline HER. A comprehensive electrode surface analysis combining transmission electron microscopy, X-ray photoelectron spectroscopy and atomic force microscopy identifies the leaching of Mo on a structural level and indicates the formation of a Ni(OH)2-rich surface area. The ultimate surface characteristics of the NiMo catalysts depend on the initial composition and the electrochemical procedure. Based on the findings, it conclude that the observed catalytic properties of NiMo alloys in HER are determined by a complex interplay of increasing roughness, available surface species and their synergies. The leaching of Mo has a proven structural effect and is considered one of several factors contributing to the enhanced catalyst activity.

Peptide hydrogel based electrochemical biosensor for simultaneous monitoring ofH2O2 and NO released from three-dimensional cultured breast cancer cells.

Anantifouling peptide hydrogel-based electrochemical biosensor was developedfor real-time monitoring of hydrogen peroxide (H2O2) and nitric oxide (NO) released by 3D cultured breast cancer cells upon drug stimulation. Platinum nanoparticles (Pt NPs) were electrodeposited on titanium mesh (Pt NPs/TM) to enhance sensitivity and shown topossess excellent electrocatalytic ability toward H2O2 and NO. The composite hydrogel formed by co-assembling of N-fluorenylmethoxycarbonyl diphenylalanine (Fmoc-FF) and a fluorine methoxycarbonyl group-functionalized Lys-(Fmoc)-Asp was coated on Pt NPs/TM electrode surface to provide cellular scaffolding. Their favorable biocompatibility promoted cell adhesion and growth, while good hydrophilicity endowed the sensor with greatly enhanced antifouling capability in complex cell culture environments. The biosensor successfully determined H2O2 and NO secretion from both non-metastatic and metastatic breast cancer cells in real time. Our results demonstrated robust associations between reactive oxygen species (ROS) and reactive nitrogen species (RNS) production and cell malignancy, with the main difference in oxidative stress between the two subtypes of cells being NO release, particularly emphasizing RNS's critical leading in driving cancer metastasis and invasion progression. This sensor holds great potential for cell-release research under the in vivo-like microenvironment and could reveal RNS as an attractive therapeutic target for treating breast cancer.

Ni–P–PTFE cathode with low surface energy for enhancing electrochemical water softening performance

ABSTRACT Efficient cathode regeneration is a significant challenge in the electrochemical water softening process. This work explores the use of an electroless plating Ni–P–PTFE electrode with low surface energy for this purpose. The Ni–P–PTFE electrode demonstrates improved self-cleaning performance at high current densities. By combining the low surface energy of the electrode with fluid flushing shear force, the precipitation rate on the Ni–P–PTFE electrode remains stable at approximately 18 g/m2·h over extended periods of operation. Additionally, the cleaning efficiency of the Ni–P–PTFE electrode surpasses that of stainless steel by 66.34%. The Ni–P–PTFE electrode can maintain a larger active area and a longer operational lifespan is attributed to its self-cleaning performance derived from low surface energy. Furthermore, the loose scale layers on the electrode surface are easily removed during electrochemical water softening processes, presenting a novel approach to cathode surface design.

Inverted Sandwich-Type e-LCR Aided by Lambda Exonuclease-RecJf Combination Enables Ultrasensitive Detection of Low-Frequency EGFR-L858R Mutation in NSCLC.

Highly sensitive detection of low-frequency EGFR-L858R mutation is particularly important in guiding targeted therapy of nonsmall-cell lung carcinoma (NSCLC). To this end, a ligase chain reaction (LCR)-based electrochemical biosensor (e-LCR) with an inverted sandwich-type architecture was provided by combining a cooperation of lambda exonuclease-RecJf exonuclease (λ-RecJf exo). In this work, by designing a knife-like DNA substrate (an overhang ssDNA part referred to the "knife arm") and introducing the λ-RecJf exo, the unreacted DNA probes in the LCR were specially degraded while only the ligated products were preserved, after which the ligated knife-like DNA products were hybridized with capture probes on the gold electrode surface through the "knife arms", forming the inverted sandwich-type DNA structure and bringing the methylene blue-label close to the electrode surface to engender the electrical signal. Finally, the sensitivity of the e-LCR could be improved by 3 orders of magnitude with the help of the λ-RecJf exo, and due to the mutation recognizing in the ligation site of the employed ligase, this method could detect EGFR-L858R mutation down to 0.01%, along with a linear range of 1 fM-10 pM and a limit detection of 0.8 fM. Further, the developed method could distinguish between L858R positive and negative mutations in cultured cell samples, tumor tissue samples, and plasma samples, whose accuracy was verified by the droplet digital PCR, holding a huge potential in liquid biopsy for precisely guiding individualized-treatment of NSCLC patients with advantages of high sensitivity, low cost, and adaptability to point-of-care testing.

Electrochemical goniometry: keystone reactivity at the three-phase boundary

AbstractContact angles of liquid, spherical cap droplets immobilised on an electrode surface and bathed by a fluid are important, quantifiable measures of the liquid/fluid interfacial tension. Optical goniometry, even if computer assisted, suffers when the contact angle is 10° or less. In this work, an alternative method of measurement is considered: electrochemical techniques (voltammetry and chronoamperometry), which rely on the transport of material from within the droplet to the conductive surface. As a result of the reactions that take place at the triple phase boundary, these are demonstrated to provide information on the size and the shape of the droplet, including its contact angle, for the cases when the droplets have a redox analyte and either have a supporting electrolyte, or not. The voltammetric behaviour is seen to change from exhaustive, thin film characteristics, to quasi-steady-state signals as the droplet becomes bigger, or the scan rate becomes larger, or diffusion of the redox material inside the droplet becomes slower. One of the surprising outcomes is that there is a zone of planar diffusion only in the case of the supported droplets, with both the droplet size and its contact angle determining whether this is seen at conventional combinations of scan rates and diffusion coefficients. Experimental data are provided which emphasize key features pertaining to the nature of the redox system and illustrate the facile nature of the contact angle estimation process, albeit to within 10% uncertainty.

Electrochemiluminescence Lateral Flow Immunoassay Using Ruthenium(II) Complex‐Loaded Dendritic Mesoporous Silica Nanospheres for Highly Sensitive and Quantitative Detection of SARS‐CoV‐2 Nucleocapsid Protein

AbstractLateral flow immunoassays (LFIA) are widely used for the cost‐effective and rapid detection of diverse analytes. However, traditional LFIA suffers from difficulties in providing quantitative results and has low sensitivity. Herein, LFIA is combined with electrochemiluminescence (ECL), a leading transduction technique with high sensitivity and wide dynamic range, to achieve highly sensitive and quantitative detection of severe acute respiratory syndrome coronavirus nucleocapsid protein (SARS‐CoV‐2 N protein). Ruthenium(II)‐based complexes are synthesized and loaded into dendritic mesoporous silica nanospheres (PEI‐Ru/dSiO2), which possessed central‐radial pore channels and served as tags for ECL‐LFIA. The electrodes are fabricated on a nitrocellulose (NC) membrane, which simplifies the structure of the ECL‐LFIA. PEI‐Ru/dSiO2 is captured on the electrode surface via a sandwich immunoreaction, which enhances the ECL signal by decreasing the distance between PEI‐Ru/dSiO2 and the electrode surface. Using 2,2‐bis(hydroxymethyl)‐2,2′,2′'‐nitrilotriethanol (BIS‐TRIS) as coreactant, the ECL‐LFIA is used for detecting SARS‐CoV‐2 N protein, with a linear range of 1–104 ng mL−1 and a limit of detection (LOD) of 0.52 ng mL−1. ECL‐LFIA can also be used to detect analytes in complex matrices. These results demonstrate that the prepared ECL‐LFIA has great potential as a point‐of‐care testing platform for the rapid and quantitative detection of disease biomarkers.

Optimized Electrode/Electrolyte Interface Engineering for Dendrite‐Free Al Anode and Self‐Activated Graphite Cathode

AbstractRechargeable aluminum batteries (RABs) have garnered attention owing to their impressive theoretical capacity, outstanding safety features, and abundant Al reserves, thereby positioning them as a potential alternative and supplement to fixed energy storage. Nonetheless, RABs still suffer from issues, such as poor anode stability stemming from the corrosivity of the chloral aluminate ionic liquid electrolyte (ILs) and subpar wettability of the cathode. To address these issues, the proposed electrolyte interfacial engineering involves the nonionic surfactant (F127) as an interfacial optimizer in ILs, simultaneously modulating the anode–electrolyte and cathode–electrolyte interfaces. Systematic experiments and theoretical analyses validate that F127 preferentially adsorbs on the electrode surface, forming a dense and uniform adsorption layer. The F127 layer can effectively mitigate the corrosion of ILs on the Al anode and regulate the current density to achieve uniform Al deposition. Furthermore, F127 enhances the wettability between the cathode and ILs, preventing the collapse of the graphite structure and enhancing the active material's utilization. The Al//FG full battery assembled with F127 modifying ILs (F127‐0.5) is able to retain a specific capacity of 104.9 mAh g−1 after 1600 cycles, which is higher than ILs (69.0 mAh g−1). This electrolyte interface modification strategy holds considerable practical significance for achieving long‐lifespan and high‐capacity RABs.

Hybrid Training System Consisting of Synchronized Neuromuscular Electrical Stimulation for Voluntary Exercise Using an Articular Motion Sensor.

Neuromuscular electrical stimulation (NMES) is widely used for improving muscle strength, preventing muscle atrophy, and decreasing pain. Recently, NMES has become a substitute for exercise therapy for metabolism improvement and functional capacity improvement. However, NMES has several disadvantages. First, slow-twitch muscle contractions are insufficient because the recruitment pattern of NMES does not obey Henneman's size principle. Second, when using surface electrodes, it is difficult to contract deep skeletal muscles at the application site. Third, electrical stimulation causes discomfort. Therefore, we devised a simultaneous combination of NMES and voluntary muscle contractions to overcome the weak points of NMES. A hybrid training system (HTS) that resists the motion of a volitionally contracting agonist muscle with force generated by its electrically stimulated antagonist was developed as a technique to combine the application of NMES and volitional contractions. This motion sensor makes it possible to simultaneously combine voluntary movements with NMES. Our HTS synchronizes with voluntary movements, enhancing safety and reducing discomfort. This HTS enhances the exercise effect of even simple exercise. So far, our HTS has been reported to be effective for muscle strength enhancement, prevention of muscle atrophy, improvement of physical function, pain relief, enhancement of physical fitness, and improvement of metabolic function. HTS are expected to be useful methods in environments where sufficient exercise load is not available or for individuals with low exercise tolerance.

Copper(II)-Tannic Acid@Cu with In Situ Grown Gold Nanoparticles as a Bifunctional Matrix for Facile Construction of Label-Free and Ultrasensitive Electrochemical cTnI Immunosensor.

Sensitive detection of cardiac troponin I (cTnI) is of great significance in the diagnosis of a fatal acute myocardial infarction. A redox-active nanocomposite of copper(II)-tannic acid@Cu (CuTA@Cu) was herein prepared on the surface of a glassy carbon electrode by electrochemical deposition of metallic copper combined with a metal stripping strategy. Then, HAuCl4 was in situ reduced to gold nanoparticles (AuNPs) by strong reductive catechol groups in the TA ligand. The AuNPs/CuTA@Cu composite was further utilized as a bifunctional matrix for the immobilization of the cTnI antibody (anti-cTnI), producing an electrochemical immunosensor. Electrochemical tests show that the immunoreaction between anti-cTnI and target cTnI can cause a significant reduction of the electrochemical signal of CuTA@Cu. It can be attributed to the insulating characteristic of the immunocomplex and its barrier effect to the electrolyte ion diffusion. From the signal changes of CuTA@Cu, cTnI can be analyzed in a wide range from 10 fg mL-1 to 10 ng mL-1, with an ultralow detection limit of 0.65 fg mL-1. The spiked recovery assays show that the immunosensor is reliable for cTnI determination in human serum samples, demonstrating its promising application in the early clinical diagnosis of myocardial infarction.

Why Is Surface-Enhanced Raman Scattering Insensitive to Liquid Water?

Surface-enhanced Raman scattering (SERS) is widely recognized as a remarkably powerful analytical technique that enables trace-level detection of organic molecules on a metal surface in aqueous systems with negligible spectral interference of water. This insensitivity of SERS to liquid water is violated in a restrictive manner under specific electrochemical conditions. However, the origin of such different SERS sensitivities to liquid water remains unclear. Here, we show that hydrogen-bond networks of water play a pivotal role in losing SERS enhancement for liquid water, and SERS detection of water requires local defects in the hydrogen-bond networks, which are formed around hydration shells of solute ions or on a polarized electrode surface. This work gives a new perspective on in situ SERS investigations in aqueous systems, including electrochemical and biological reactions.

Electric Discharge Between a Metal Cathode and a Liquid Non-Metal Anode

Gas-discharge plasma generated between a metal cathode and a liquid non-metallic anode at atmospheric pressure has been studied. The discharge is ignited by immersing the metal electrode in the electrolyte. The types and shapes of plasma structures generated in the interelectrode gap and their electrical parameters are considered. The results of thermographic analysis of the electrode surface under discharge conditions are presented. Using emission spectroscopy, the plasma composition, electron concentration and temperature of the heavy component were studied.

Simultaneous voltammetric detection of acetaminophen and levofloxacin based on barley leaves derived carbon decorated with gold nanoparticles

In this study, barley leaves were used as biomass precursor to prepare the ZnCl2 activated barley leaves derived carbon by the carbonization under N2 atmosphere at high temperature (ZnAC). The gold nanoparticles were synthesized in situ on the surface of ZnAC (AuNPs/ZnAC). The as-prepared AuNPs/ZnAC composite was characterized by SEM, Raman spectroscopy, XRD et. al. The AuNPs/ZnAC composite was drop-cast onto the surface of a glassy carbon electrode to fabricate an electrochemical sensing platform for the simultaneous determination of acetaminophen (AC) and levofloxacin (LEV). The results of electrochemical experiments showed that ZnAC and AuNPs had a synergetic electrocatalytic effect on the oxidation of AC and LEV. The oxidation peak potentials of AC and LEV were at 0.57 and 1.02 V, respectively. The proposed sensor allowed the simultaneous quantification of AC and LEV two linear intervals: in the ranges of 0.1–15 and 15–300 μM for AC and 0.1–20 and 20–300 μM for LEV with the detection limits of 0.02 and 0.03 μM, respectively. In addition, the sensor has the advantages of low cost, high sensitivity, simple preparation and environmental friendliness, as well as good selectivity, stability and reproducibility. We measured AC and LEV in artificial urine, tap water, and lake water, and the recoveries were between 93 % and 109 %, indicating that the sensor has good application prospects in biomedicine and environmental protection.

Enhanced Electrocatalysis on Copper Nanostructures: Role of the Oxidation State in Sulfite Oxidation.

The influence of surface morphology and the oxidation state on the electrocatalytic activity of nanostructured electrodes is well recognized, yet disentangling their individual roles in specific reactions remains challenging. Here, we investigated the electrooxidation of sulfite ions in an alkaline environment using cyclic voltammetry on copper oxide nanostructured electrodes with different oxidation states and morphologies but with similar active areas. To this aim, we synthesized nanostructured Cu films made of nanoparticles or nanorods on top of glassy carbon electrodes. Our findings showed an enhanced sensitivity and a lower detection threshold when utilizing Cu(I) over Cu(II). Density functional theory-based thermochemical analysis revealed the underlying oxidation mechanism, indicating that while the energy gain associated with the process is comparable for both oxide surfaces, the desorption energy barrier for the resulting sulfate molecules is three times higher on Cu(II). This becomes the limiting step of the reaction kinetics and diminishes the overall electrooxidation efficiency. Our proposed mechanism relies on the tautomerization of hydroxyl groups confined on the surface of Cu-based electrodes. This mechanism might be applicable to electrochemical reactions involving other sulfur compounds that hold technological significance.

Electrolyte-Electrocatalyst Interfacial Effects of Polymeric Materials for Tandem CO2 Capture and Conversion Elucidated Using In Situ Electrochemical AFM.

Integrating CO2 capture and electrochemical conversion has been proposed as a strategy to reduce the net energy required for CO2 regeneration in traditional CO2 capture and conversion schemes and can be coupled with carbon-free renewable electricity. Polyethylenimine (PEI)-based materials have been previously studied as CO2 capture materials and can be integrated in these reactive capture processes. PEI-based electrolytes have been found to significantly increase the CO2 loading, and impact selectivity and rate of product formation when compared to the conventional aqueous electrolytes. However, the influence of these materials at the catalyst-electrode interface is currently not well understood. In this study, PEI-based electrolytes were prepared and their impact on the morphology of a silver electrode performing electrochemical CO2 reduction (CO2R) was studied using in situ electrochemical atomic force microscopy (EC-AFM). The presence of PEI on the electrode surface could be distinguished based on nanomechanical properties (DMT modulus), and changes were observed as negative polarization was applied, revealing a reorganization of the PEI chains due to electrostatic interactions. These changes were impacted by the electrolyte composition, including the addition of supporting electrolyte KHCO3 salt, as well as CO2 captured by the PEI-based electrolyte, which minimized the change in surface mechanical properties and degree of PEI alignment on the electrode surface. The changes in surface mechanical properties were also dependent on the PEI polymer length, with higher molecular weight PEI showing different reconfiguration than the shorter polymer brushes. The study highlights that the choice of polymer material, the electrolyte composition, and CO2 captured impact the near-electrode environment, which has implications for CO2R, and presents EC-AFM as a new tool that can be used to probe the dynamic behavior of these interfaces during electrocatalysis.

Electrochemical treatment of 4-chlorophenol by three-dimensional electrode reactors packed with plastic particles electrodes

The three-dimensional electrode reactors (TDER) filled with surface-modified plastic particles electrodes, was much more effective on electrolyzing 4-chlorophenol wastewater than by conventional electrolysis. The experimental results indicated that about 96.8 % of 4-chorophenol was degraded effectively, it was possibly decomposed into aromatic organic compounds and small-molecular organic acids by hydroxyl radicals generated on the surfaces of electrodes, and the biodegradability of treated 4-chlorophenol wastewater was also much more improved than that of the untreated, which would be more easily biologically degraded by the subsequent conventional activated sludge process. Furthermore, the 4-chorophenol wastewater could be co-degraded with high-concentration nitrate effectively, both 2-chlorophenol and 2,4-dichorophenol wastewaters were also similarly decomposed.

ZnS/MXene/CdS heterostructure modified electrode for ultrasensitive miRNA-21 assay with signal amplified photoelectrochemical strategy

The early-stage detection of microRNA (miRNA) holds significant value for clinical diagnosis of tumor. In this study, a highly sensitive miRNA detection platform is developed using a photoelectrochemical sensing system based on layer-by-layer (LBL) assembled ZnS/MXene/CdS (ZMC) heterostructure electrode. By incorporating ultrathin and highly conductive MXene, the ZMC electrode exhibits robust photocurrent signals upon exposure to light. The electrode is further modified HS-H1 DNA via disulfide bonds.With the help of auxiliary H2 DNA, a target miRNA-21 triggered catalytic hairpin assembly (CHA) amplification reaction is realized on the electrode surface through complementary base pairing. Then, manganese porphyrin (MnPP) is introduced to the formed double-stranded DNA after CHA reaction to catalyze the conversion of 4-chloro-1-naphthol (4-CN) to benzo-4-chloro-hexanedione (4-CD) precipitate in the presence of hydrogen peroxide, which leads to a significant decrease in photocurrent signals. As a result, the sensor demonstrates a reliable linear correlation in miRNA-21 detection with detection limits as low as 0.36 fM. The recoveries of miRNA-21 in human serum samples ranged from 98.27 % to 101.35 % with RSD values below 3.67 % suggest the reliability and practicality of this method. Therefore it shows great potential for the construction and application of highly sensitive photoelectrochemical biosensors in clinical sample detection.

Synthesis and characterization of polysaccharide-cryogel and its application to the electrochemical detection of DNA

The main goal of our study is to demonstrate the applicability of the PPy-cryogel-modified electrodes for electrochemical detection of DNA. First, a polysaccharide-based cryogel was synthesized. This cryogel was then used as a template for chemical polypyrrole synthesis. This prepared polysaccharide-based conductive cryogel was used for electrochemical biosensing on DNA. Carrageenan (CG) and sodium alginate (SA) polysaccharides, which stand out as biocompatible materials, were used in cryogel synthesis. Electron transfer was accelerated by polypyrrole (PPy) synthesized in cryogel networks. A 2B pencil graphite electrode with a diameter of 2.00 mm was used as a working electrode. The prepared polysaccharide solution was dropped onto a working electrode as a support material to improve the immobilization capacity of biomolecules and frozen to complete the cryogelation step. PPy synthesis was performed on the electrodes whose cryogelation process was completed. In addition, the structures of cryogels synthesized on the electrode surface were characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Surface characterization of the modified electrodes was performed by energy-dispersive X-ray spectroscopy (EDX) analysis. Electrochemical determination of fish sperm DNA (fsDNA) was performed using a PPy-cryogel-modified electrode. The use of a porous 3D cryogel intermediate material enhanced the signal by providing a large surface area for the synthesis of PPy and increasing the biomolecule immobilization capacity. The detection limit was 0.98 µg mL−1 in the fsDNA concentration range 2.5–20 µg mL−1. The sensitivity of the DNA biosensor was estimated to 14.8 µA mM−1 cm−2. The stability of the biosensor under certain storage conditions was examined and observed to remain 66.95% up to 45 days.Graphical