Electrochemical profiling of natural furanocoumarins: DNA interaction dynamics of oxypeucedanin and prantschimgin.

Background and purpose: In this study, we present an electrochemical sensor for the detection of oxypeucedanin (Oxyp) and prantschimgin (Pra), two natural furanocoumarin derivatives. The determination of the effects of these molecules on DNA is important to be potential drug candidates. Our research focused on exploring the electrochemical behaviour of these compounds and their interaction with DNA. Experimental approach: The electrochemical properties of Oxyp and Pra were systematically analyzed by evaluating their oxidation currents. Changes in the oxidation currents and peak potentials of guanine bases were monitored before and after interaction in the solution phase and at the electrode surface. Key results: The limit of detection (LOD) and limit of quantitation (LOQ) for Oxyp were determined to be 1.3 and 4.3 µg/mL, respectively. For Pra, the LOD and LOQ were found to be 20 and 68 µg/mL, respectively. Stability studies demonstrated that the Oxyp solution retained its oxidation capacity for over a month, whereas the Pra solution retained its oxidation capacity for nearly 120 min. Our findings suggest that Oxyp interacts with dsDNA, potentially through electrostatic interactions, showing promise as a potential drug candidate targeting DNA. On the other hand, the interaction of Pra with dsDNA requires further exploration to fully understand its mode of action. Conclusion: The electrochemical sensor developed in this study provides a reliable and efficient method for detecting and analysing the interaction of these natural compounds with dsDNA. Our research contributes to advancing the understanding of the interaction between natural furanocoumarins and dsDNA, laying the groundwork for the design and development of novel and effective DNA-targeted drugs.

Electrochemical Properties of Fused Pyrimidine-Triazole Heterocyclic Molecules as Novel Drug Candidates.

Objectives: Triazolopyrimidinones are compounds used in medicinal chemistry. In this study, three novel triazolopyrimidinone derivatives were synthesized as drug candidates: (5-(chloromethyl)-2-(4-methoxyphenyl)-[1,2,4]triazolo[1,5-a]pyrimidin-7(3H)-one) (S1-TP), 2-(4-methoxyphenyl)-5-(piperidinomethyl)-[1,2,4]triazolo[1,5-a]pyrimidin-7(3H)-one) (S2-TP), and 2-(4-methoxyphenyl)-5-(morpholinomethyl)-[1,2,4]triazolo[1,5-a] pyrimidin-7(3H)-one) (S3-TP). Their electrochemical properties were investigated for the first time using voltammetric techniques on carbon graphite electrodes. Moreover, stability tests for each drug candidate were performed on different days. After revealing the electrochemical properties of the drug candidates, their effect on double-stranded (ds) DNA was examined by measuring the oxidation currents of the guanine of dsDNA before and after the interaction. Materials and Methods: An electrochemical setup that included a pencil graphite electrode as the working electrode, an Ag/AgCl reference electrode, and a platinum wire as the auxiliary electrode was used in this study. Experiments for optimum pH, scan rate, and concentration of drug candidates were conducted. The interaction between Ss-TP and dsDNA was evaluated using differential pulse voltammetry. The stability of each drug candidate was tested on various days. Results: A comprehensive characterization of the S1-TP, S2-TP, and S3-TP compounds was performed for the first time. This study showed that the electrochemical oxidation of S1-TP and S2-TP was irreversible and diffusion-controlled. In addition, the transfer of electrons in S3-TP was controlled by adsorption. The interaction between Ss-TP and dsDNA resulted in notable changes in the peak potentialof dsDNA. The dsDNA peak potential shifted negatively after interaction with S1-TP, S2-TP, and S3-TP. Under optimum conditions, the detection limits for S1-TP, S2-TP, and S3-TP were 1.5 µg/mL, 1.0 µg/mL, and 2.0 µg/mL, respectively. Conclusion: From our experimental data, we concluded that these molecules can be used as drug molecules because of their remarkable effects on DNA.

Electrochemical investigation of hydroxyapatite-lanthanum strontium cobalt ferrite composites (HA-LSCF) for SARS-CoV-2 aptasensors.

The hydroxyapatite-lanthanum strontium cobalt ferrite (HA-LSCF) composite showed a good response on a screen-printed carbon electrode (SPCE) electrochemical aptasensor to detect SARS-CoV-2. SPCE/HA-LSCF with a thiolated aptamer has a strong affinity for the SARS-CoV-2 spike RBD protein. This occurs due to the binding of -SH to the HA-positive region. In the presence of LSCF, which is conductive, an increase in electron transfer from the redox system [Fe(CN)6]3-/4- occurs. The interaction of the aptamer with the RBD protein can be observed based on the decrease in the electron transfer process. As a result, the developed biosensor is highly sensitive to the SARS-CoV-2 spike RBD protein with a linear range of 0.125 to 2.0 ng mL-1, a detection limit of 0.012 ng mL-1, and a quantification limit of 0.040 ng mL-1. The analytical application of the aptasensor demonstrates its feasibility in the analysis of saliva or swab samples.

Plasmonic Functional Assay Platform Determines the Therapeutic Profile of Cancer Cells.

Functional assay platforms could identify the biophysical properties of cells and their therapeutic response to drug treatments. Despite their strong ability to assess cellular pathways, functional assays require large tissue samples, long-term cell culture, and bulk measurements. Even though such a drawback is still valid, these limitations did not hinder the interest in these platforms for their capacity to reveal drug susceptibility. Some of the limitations could be overcome with single-cell functional assays by identifying subpopulations using small sample volumes. Along this direction, in this article, we developed a high-throughput plasmonic functional assay platform to identify the growth profile of cells and their therapeutic profile under therapies using mass and growth rate statistics of individual cells. Our technology could determine populations' growth profiles using the growth rate data of multiple single cells of the same population. Evaluating spectral variations based on the plasmonic diffraction field intensity images in real time, we could simultaneously monitor the mass change for the cells within the field of view of a camera with the capacity of > ∼500 cells/h scanning rate. Our technology could determine the therapeutic profile of cells under cancer drugs within few hours, while the classical techniques require days to show reduction in viability due to antitumor effects. The platform could reveal the heterogeneity within the therapeutic profile of populations and determine subpopulations showing resistance to drug therapies. As a proof-of-principle demonstration, we studied the growth profile of MCF-7 cells and their therapeutic behavior to standard-of-care drugs that have antitumor effects as shown in the literature, including difluoromethylornithine (DFMO), 5-fluorouracil (5-FU), paclitaxel (PTX), and doxorubicin (Dox). We successfully demonstrated the resistant behavior of an MCF-7 variant that could survive in the presence of DFMO. More importantly, we could precisely identify synergic and antagonistic effects of drug combinations based on the order of use in cancer therapy. Rapidly assessing the therapeutic profile of cancer cells, our plasmonic functional assay platform could be used to reveal personalized drug therapies for cancer patients.

Biosensor integrated brain-on-a-chip platforms: Progress and prospects in clinical translation.

Because of the brain's complexity, developing effective treatments for neurological disorders is a formidable challenge. Research efforts to this end are advancing as in vitro systems have reached the point that they can imitate critical components of the brain's structure and function. Brain-on-a-chip (BoC) was first used for microfluidics-based systems with small synthetic tissues but has expanded recently to include in vitro simulation of the central nervous system (CNS). Defining the system's qualifying parameters may improve the BoC for the next generation of in vitro platforms. These parameters show how well a given platform solves the problems unique to in vitro CNS modeling (like recreating the brain's microenvironment and including essential parts like the blood-brain barrier (BBB)) and how much more value it offers than traditional cell culture systems. This review provides an overview of the practical concerns of creating and deploying BoC systems and elaborates on how these technologies might be used. Not only how advanced biosensing technologies could be integrated with BoC system but also how novel approaches will automate assays and improve point-of-care (PoC) diagnostics and accurate quantitative analyses are discussed. Key challenges providing opportunities for clinical translation of BoC in neurodegenerative disorders are also addressed.

Interaction of nickel ferrite nanoparticles with nucleic acids.

In this article, we introduced an electrochemical biosensor employing graphite electrodes (GE) decorated with Nickel ferrite (NiFe2O4) nanoparticles for nucleic acid detection. NiFe2O4 nanoparticles in a narrow size distribution were synthesized with co-precipitation technique. Their chemical and crystallographic properties were characterized with FTIR and X-ray spectroscopies. Nanoparticle size distribution and hydrodynamic diameter were determined with particle size analyzer. Elemental content and purity of nanoparticles were analyzed with EDX analysis. Our analyses showed a diameter of ~10 nm for NiFe2O4 nanoparticles. Electrochemical properties of NiFe2O4 nanoparticles were examined with different analysis methods. Conductivity properties of NiFe2O4 nanoparticles were investigated with Cyclic Voltammetry (CV), which confirmed that nanoparticles on GE surface have a high surface area and conductivity. More importantly, in this article, the interactions between NiFe2O4 nanoparticles and double stranded DNA (dsDNA), single stranded DNA (ssDNA), and RNA were for the first time examined using Differential Pulse Voltammetry (DPV), CV, and Electrochemical Impedance Spectroscopy (EIS). Oxidation peak currents of NiFe2O4 nanoparticles and guanine bases of dsDNA, ssDNA, and RNA showed that NiFe2O4 nanoparticles effectively interacts with nucleic acids via an electrostatic mode.

Electrochemical Detection of Linagliptin and its Interaction with DNA

Objectives: Linagliptin (Lin) is a drug used in treatment of type 2 diabetes mellitus. In this study, the electrochemical detection of Lin and its interaction with DNA was analyzed for the first time using voltammetric methods by measuring the oxidation currents of the adenine bases of DNA before and after the interaction. In addition, the electrochemical properties of the Lin were studied. Materials and Methods: The interaction between Lin and DNA was evaluated using differential pulse voltammetry. A three-electrode system comprising of a pencil graphite electrode as the working electrode, reference electrode (Ag/AgCl), and platinum wire as the auxiliary electrode was used in the electrochemical studies. Experimental conditions, such as the concentration, pH of the supporting electrolyte, and immobilization time were optimized to obtain maximum analytical signals. Results: The adenine bases of DNA were evaluated as an analytical signal obtained at approximately +1.2 V vs. Ag/AgCl. After the Lin-DNA interaction, the oxidation currents of adenine decreased as proof of interaction. No reports have been published on Lin interacting with DNA. Based on our results, a diffusion-controlled irreversible redox process involving independent oxidation was revealed for Lin. Under optimum conditions, the detection limit was 6.7 µg/mL for DNA and 21.5 µg/mL for Lin. Based on the observations, Lin has a toxic effect on DNA. Conclusion: We successfully demonstrated that Lin interacts with DNA, and its influence on DNA could play a vital role in the medical effect of the drug.

Handheld plasmonic biosensor for virus detection in field-settings.

After World Health Organization (WHO) announced COVID-19 outbreak a pandemic, we all again realized the importance of developing rapid diagnostic kits. In this article, we introduced a lightweight and field-portable biosensor employing a plasmonic chip based on nanohole arrays integrated to a lensfree-imaging framework for label-free detection of viruses in field-settings. The platform utilizes a CMOS (complementary metal-oxide-semiconductor) camera with high quantum efficiency in the spectral window of interest to monitor diffraction field patterns of nanohole arrays under the uniform illumination of an LED (light-emitting diode) source which is spectrally tuned to the plasmonic mode supported by the nanohole arrays. As an example for the applicability of our biosensor for virus detection, we could successfully demonstrate the label-free detection of H1N1 viruses, e.g., swine flu, with medically relevant concentrations. We also developed a low-cost and easy-to-use sample preparation kit to prepare the surface of the plasmonic chip for analyte binding, e.g., virus-antibody binding. In order to reveal a complete biosensor technology, we also developed a user friendly Python™ - based graphical user interface (GUI) that allows direct access to biosensor hardware, taking and processing diffraction field images, and provides virus information to the end-user. Employing highly sensitive nanohole arrays and lensfree-imaging framework, our platform could yield an LOD as low as 103 TCID50/mL. Providing accurate and rapid sensing information in a handheld platform, weighing only 70 g and 12 cm tall, without the need for bulky and expensive instrumentation, our biosensor could be a very strong candidate for diagnostic applications in resource-poor settings. As our detection scheme is based on the use of antibodies, it could quickly adapt to the detection of different viral diseases, e.g., COVID-19 or influenza, by simply coating the plasmonic chip surface with an antibody possessing affinity to the virus type of interest. Possessing this ability, our biosensor could be swiftly deployed to the field in need for rapid diagnosis, which may be an important asset to prevent the spread of diseases before turning into a pandemic by isolating patients from the population.

Refractive Index Sensing for Measuring Single Cell Growth.

Accessing cell growth on adhesive substrates is critical for identifying biophysical properties of cells and their therapeutic response to drug therapies. However, optical techniques have low sensitivity, and their reliability varies with cell type, whereas microfluidic technologies rely on cell suspension. In this paper, we introduced a plasmonic functional assay platform that can precisely measure cell weight and the dynamic change in real-time for adherent cells. Possessing this ability, our platform can determine growth rates of individual cells within only 10 min to map the growth profile of populations in short time intervals. The platform could successfully determine heterogeneity within the growth profile of populations and assess subpopulations exhibiting distinct growth profiles. As a proof of principle, we investigated the growth profile of MCF-7 cells and the effect of two intracellular metabolisms critical for their proliferation. We first investigated the negative effect of serum starvation on cell growth. We then studied ornithine decarboxylase (ODC) activity, a key enzyme which is involved in proliferation, and degraded under low osmolarity that inhibits cell growth. We successfully determined the significant distinction between growth profiles of MCF-7 cells and their ODC-overproducing variants that possess strong resistance to the negative effects of low osmolarity. We also demonstrated that an exogenous parameter, putrescine, could rescue cells from ODC inhibition under hypoosmotic conditions. In addition to the ability of accessing intracellular activities through ex vivo measurements, our platform could also determine therapeutic behaviors of cancer cells in response to drug treatments. Here, we investigated difluoromethylornithine (DFMO), which has antitumor effects on MCF-7 cells by inhibiting ODC activity. We successfully demonstrated the susceptibility of MCF-7 cells to such drug treatment, while its DFMO-resistant subpopulation could survive in the presence of this antigrowth agent. By rapidly determining cell growth kinetics in small samples, our plasmonic platform may be of broad use to basic research and clinical applications.

Tissue Adhesives: From Research to Clinical Translation.

Sutures, staples, clips and skin closure strips are used as the gold standard to close wounds after an injury. In spite of being the present standard of care, the utilization of these conventional methods is precarious amid complicated and sensitive surgeries such as vascular anastomosis, ocular surgeries, nerve repair, or due to the high-risk components included. Tissue adhesives function as an interface to connect the surfaces of wound edges and prevent them from separation. They are fluid or semi-fluid mixtures that can be easily used to seal any wound of any morphology - uniform or irregular. As such, they provide alternatives to new and novel platforms for wound closure methods. In this review, we offer a background on the improvement of distinctive tissue adhesives focusing on the chemistry of some of these products that have been a commercial success from the clinical application perspective. This review is aimed to provide a guide toward innovation of tissue bioadhesive materials and their associated biomedical applications.

Pathogen detection with electrochemical biosensors: Advantages, challenges and future perspectives.

Detection of pathogens, e.g., bacteria and viruses, is still a big challenge in analytical medicine due to their vast number and variety. Developing strategies for rapid, inexpensive, specific, and sensitive detection of the pathogens using nanomaterials, integrating with microfluidics devices, amplification methods, or even combining these strategies have received significant attention. Especially, after the health-threatening COVID-19 outbreak, rapid and sensitive detection of pathogens became very critical. Detection of pathogens could be realized with electrochemical, optical, mass sensitive, or thermal methods. Among them, electrochemical methods are very promising by bringing different advantages, i.e., they exhibit more versatile detection schemes and real-time quantification as well as label-free measurements, which provides a broader application perspective. In this review, we discuss the recent advances for the detection of bacteria and viruses using electrochemical biosensors. Moreover, electrochemical biosensors for pathogen detection were broadly reviewed in terms of analyte, bio-recognition and transduction elements. Different fabrication techniques, detection principles, and applications of various pathogens with the electrochemical biosensors were also discussed.

Synthesis and characterization of nanoceria for electrochemical sensing applications.

Nanoceria (cerium oxide nanoparticles: CeO2-NPs) has received significant attention due to its biocompatibility, good conductivity, and the ability to transfer oxygen. Nanoceria has been widely used to develop electrochemical sensors and biosensors as it could increase response time, sensitivity, and stability of the sensor. In this review, we discussed synthesis methods, and the recent applications employing CeO2-NPs for electrochemical detection of various analytes reported in the most recent four years.

Correction: Synthesis and characterization of nanoceria for electrochemical sensing applications.

[This corrects the article DOI: 10.1039/D1RA00637A.].

Photonic crystal and plasmonic nanohole based label-free biodetection.

Photonic crystals and plasmonic nanohole arrays are the conventional substrates for label-free biodetection applications. In this article, we readdressed these systems in terms of their sensing capability and provided a broad picture for a selection mechanism of optimum parameters providing strong sensing signals. We first investigated the physical origin of the transmission resonances supported by the two systems, which is the core of the label-free sensing mechanism, relying on strong light-matter interactions. We conducted an extensive theoretical study on optical and sensing properties of the two systems, e.g., linewidth of the optical modes, refractive index sensitivity and figure-of-merit capacities. Our theoretical analyses provided a rule-of-thumb method for the selection of geometrical device parameters of the two systems. In order to experimentally investigate the sensing properties, we fabricated the two systems via a lift-off free fabrication method based on electron beam lithography, where the plasmonic nanohole arrays are realized by covering the phonic crystal surface with a thin metal. As an example, we demonstrated the sensing strength of two systems with identical dimensions by monitoring the spectral variations within their optical responses. We also performed label-free sensing experiments through detection of protein mono- and bilayers, where the geometrical parameters favor the plasmonic sensor system. Integrating a high-resolution optical read-out scheme with a multi-spectral data tracking technique, we achieved an experimentally minimum detectable protein concentration as low as 200 pg/mL for the plasmonic nanohole array and 1 ng/mL for the photonic crystal-based sensing platform.

Nitration of tyrosine and its effect on DNA hybridization.

One major marker of nitrosative stress is the formation of 3-Nitrotyrosine (3-NT) from Tyrosine (Tyr) by adding a nitro group (-NO2) with nitrating agents. Nitration of Tyr often causes loss of protein activity and is linked with many diseases. In this article, we detect 3-NT and discriminate it from Tyr with Differential Pulse Voltammetry (DPV) as it is a very important biomarker. We first examined redox (oxidation/reduction) properties and stability of 3-NT in detail. Second, we provided the Tyr and 3-NT discrimination with DPV and compared with the chromatography. We then explored the interaction of 3-NT and DNA oligonucleotides. Our findings demonstrate that 3-NT can be used as a new electrochemical indicator, which is able to detect hybridization of probe (single stranded DNA-ssDNA) and hybrid (double stranded DNA-dsDNA) both via 3-NT reduction and guanine oxidation signal changes at the same time. The signal differences enabled us to distinguish ssDNA and dsDNA without using a label or a tag. Moreover, we achieved to detect hybridization of DNA by using the reduction signal of 3-NT obtained at -0.4V vs. Ag/AgCl. More importantly, we observed the changes of the reduction signals of 3-NT after the interaction of probe and hybrid sequences. We showed that 3-NT signal decreases more with hybrid than the probe. Our platform, for the first time, demonstrates the detection of hybridization both guanine oxidation and indicator reduction signal changes at the same time. Moreover, we, for the first time, demonstrated the interaction between 3-NT and DNA.

Cystic Fibrosis Mutation Detection with SPR Biosensor in Real Samples via Multiple Surfaces Binding Method.

AIM AND OBJECTIVE: Surface Plasmon Resonance (SPR) based biosensor system was developed for the detection of Delta F508 (ΔF508del) Cystic Fibrosis (CF) mutation in both synthetic and real samples. MATERIAL AND METHOD: In order to provide an effective hybridization between probe and the Polymerase Chain Reaction (PCR) amplicons (target), streptavidin was bound to the surface and biotin-tag probe was sent to the streptavidin-coated surface. For the target preparation, blood samples were collected from the patients who suffer from CF. Following the DNA isolation; samples were amplified with PCR with biotin-tag. Before sending the biotin-tag PCR amplicons onto the modified surface, amplicons were also interacted with the helper oligonucleotides to prevent re-annealing of the denatured DNA strands. This kind of 'multiple surface binding' method helps increasing the sensitivity of the detection. RESULTS: The limit of detection (S/N= 3) was calculated as 12.24 pico-mole/ml for PCR-like synthetic long target sequence and 13x105 molecules for real samples in less than half an hour. CONCLUSION: Using the both biotin-tag probe and the helper oligonucleotides together, hybridization was achieved much more efficiently than traditional denaturation protocols for real samples and biotinfree hybridization detection. To the best of our knowledge, the procedure described in this study is one of the simplest, rapid and sensitive methods for CF mutation detection with SPR based biosensor system in real samples.

Fullerene-C60-MWCNT composite film based ultrasensitive electrochemical sensing platform for the trace analysis of pyruvic acid in biological fluids.

We propose development of a novel electrochemical sensor based on fullerene-multi-walled carbon nanotubes composite film for the sensitive determination of the pyruvic acid in biological fluids. The developed sensor was characterized by cyclic voltammetry. The nanocomposite film of C60-MWCNTs on GCE exhibits electrocatalytic activity towards pyruvic acid reduction and also decreases the reduction overpotential. The influence of the optimization parameters such as pH and effect of loading of composite mixture of C60 and MWCNTs on the electrochemical performance of the sensor were evaluated. Various kinetic parameters such as electron transfer number (n=2), proton transfer number (m=2) and charge transfer coefficient (α=0.56) were also calculated. Under optimized conditions, the squarewave reduction peak current was linear over the concentration range of 2.0-55 nM with the detection and quantification limit of 0.1 nM and 0.8 nM respectively. The fabricated sensor was successfully applied to the detection of pyruvic acid in biological samples with good recovery ranging from 97.6% to 103.6%.

Gelatin methacrylate (GelMA) mediated electrochemical DNA biosensor for DNA hybridization.

In this study, an electrochemical biosensor system for the detection of DNA hybridization by using gelatin methacrylate (GelMA) modified electrodes was developed. Electrochemical behavior of GelMA modified Pencil Graphite Electrode (PGE) that serve as a functional platform was investigated by using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) and compared with those of the bare PGE. Hybridization was achieved in solution phase and guanine oxidation signal changes were evaluated. The decrease in the guanine oxidation peak currents at around +1.0 V was used as an indicator for the DNA hybridization. Also, more interestingly GelMA intrinsic oxidation peaks at around +0.7 V changed substantially by immobilization of different oligonucleotides such as probe, hybrid and control sequences to the electrode surface. It is the first study of using GelMA as a part of an electrochemical biosensor system. The results are very promising in terms of using GelMA as a new DNA hybridization indicator. Additionally, GelMA modified electrodes could be useful for detecting ultra low quantity of oligonucleotides by providing mechanical support to the bio-recognition layer. The detection limit of this method is at present 10(-12)mol. Signal suppressions were increased from 50% to 93% for hybrid with using GelMA when it was compared to bare electrode which facilitates the hybridization detection.

Tough and flexible CNT-polymeric hybrid scaffolds for engineering cardiac constructs.

In the past few years, a considerable amount of effort has been devoted toward the development of biomimetic scaffolds for cardiac tissue engineering. However, most of the previous scaffolds have been electrically insulating or lacked the structural and mechanical robustness to engineer cardiac tissue constructs with suitable electrophysiological functions. Here, we developed tough and flexible hybrid scaffolds with enhanced electrical properties composed of carbon nanotubes (CNTs) embedded aligned poly(glycerol sebacate):gelatin (PG) electrospun nanofibers. Incorporation of varying concentrations of CNTs from 0 to 1.5% within the PG nanofibrous scaffolds (CNT-PG scaffolds) notably enhanced fiber alignment and improved the electrical conductivity and toughness of the scaffolds while maintaining the viability, retention, alignment, and contractile activities of cardiomyocytes (CMs) seeded on the scaffolds. The resulting CNT-PG scaffolds resulted in stronger spontaneous and synchronous beating behavior (3.5-fold lower excitation threshold and 2.8-fold higher maximum capture rate) compared to those cultured on PG scaffold. Overall, our findings demonstrated that aligned CNT-PG scaffold exhibited superior mechanical properties with enhanced CM beating properties. It is envisioned that the proposed hybrid scaffolds can be useful for generating cardiac tissue constructs with improved organization and maturation.

Detection of Janus Kinase 2 gene single point mutation in real samples with electrochemical DNA biosensor.

Janus Kinase 2 (JAK2) gene single point mutations, which have been reported to be associated with myeloproliferative disorders, are usually detected through conventional methods such as melting curve assays, allele-specific and quantitative Polymerase Chain Reactions (PCRs). Herein, an electrochemical biosensor for the detection of a Guanine (G) to Thymine (T) transversion at nucleotide position 1849 of the JAK2 gene was reported. Due to clinical importance of this mutation, easy and sensitive tests are needed to be developed. Our aim was to design a biosensor system that is capable of detecting the mutation within less than 1h with high sensitivity. For these purposes, an electrochemical sensing system was developed based on detecting hybridization. Hybridization between probe and its target and discrimination of single point mutation was investigated by monitoring guanine oxidation signals observed at +1.0 V with Differential Pulse Voltammetry (DPV) by using synthetic oligonucleotides and Polymerase Chain Reaction (PCR) amplicons. Hybridization between probe and PCR amplicons was also determined with Electrochemical Impedance Spectroscopy (EIS). We successfully detect hybridization first in synthetic samples, and ultimately in real samples involving blood samples from patients as well as additional healthy controls. The limit of detection (S/N=3) was calculated as 44 pmol of target sequence in a 40-µl reaction volume in real samples.