Nucleic Acid Hybridization Based Electrochemical Biomolecular Sensors

Electrochemical DNA biosensors are of practical value in plant pathogen detection, and Lifeasible offers DNA biosensors based on nucleic acid hybridization as one of the means of plant pathogen analysis and detection. We use DNA as the sensitive element, fix the DNA on the electrode, and through the electrode, the biological signals of DNA interaction with nucleic acids, free radicals, compounds, etc., are transformed into detectable physical signals such as acoustic waves, electricity, light, etc. This can meet your purpose of qualitative and quantitative detection of plant pathogens.

Detection principle

We use gold-sulfur bonds or antigen- or antibody-specific interactions to immobilize a segment of single-stranded DNA (ssDNA) of a specific sequence on the electrode surface. The immobilized ssDNA is specifically recognized by ssDNA of the complementary sequence in the solution to form double-stranded DNA (dsDNA). We detect the presence of a target by recognizing changes in the electrochemical response signals of hybridization indicators for ssDNA and dsDNA and also by recognizing markers on the complementary strand. The value of the response signal changes with the concentration of the complementary sequence ssDNA. Within a certain range, the response signal is linearly related to the concentration of the substance to be tested, thus achieving the purpose of qualitative and quantitative detection of plant pathogens.

Application examples

• Sugarcane white leaf disease (SCWL) detection



• Plum pox virus (PPV) detection
  We can detect PPV by using the amide bond between the carboxyl group on the surface of the oxidation electrode of the NH2-ssDNA probe and the amino group on the ssDNA probe and recording the analytical signals generated from the hybridization using Osteryoung square wave voltammetry (OSWV), using [Fe(CN)₆]^3-/4- as the redox marker. The method was able to differentiate between healthy and susceptible plants in the concentration range of 10-50 pg/mL with a detection limit of 12.8 pg/mL, which is highly sensitive and selective, and requires a small sample size and simple operation.
• MicroRNA detection
  We have anchored DNA probes for microRNA detection on MoS₂ nanosheets to achieve sensitive detection of microRNA through the combination of DNA and RNA-specific recognition.

Electrochemical DNA biosensors use DNA probes to hybridize with complementary strand DNA or RNA through base-specific recognition, using hydrogen bonding and base stacking as non-covalent bonding forces, which can easily enable the detection of complementary strand DNA or RNA. Lifeasible offers highly sensitive and cost-effective DNA biosensors based on nucleic acid hybridization forplant pathogen detection needs. Please feel free to contact us for more information.