Gold nanogap impedimetric biosensor for precise and selective Ganoderma boninense detection

Area of Science:

• Plant Pathology
• Nanotechnology
• Biosensing

Background:

• Ganoderma species are significant wood-rotting fungi causing root and stem rot in various plants, impacting agriculture and forestry.
• Identifying infectious Ganoderma species is challenging due to complex chemistry, requiring time-consuming bioassays.
• Current detection methods for plant pathogens are often limited in sensitivity and speed.

Purpose of the Study:

• To develop a highly sensitive and specific biosensor for the rapid identification of infectious Ganoderma species.
• To utilize sub-20-nm gold electrodes for enhanced molecular detection capabilities.
• To establish a new diagnostic tool for early detection of Ganoderma infections in plantation crops.

Main Methods:

• Fabrication of sub-20-nm gold electrodes using chemically controlled etching (2, 10, and 20 nm).
• Development of a nanogap electrode sensor using photolithography and size reduction techniques.
• Surface modification with synthesized *Ganoderma boninense* target DNA for molecular interaction.

Main Results:

• The developed sensor achieved a detection limit of 0.001 mol/L, seven times lower than existing devices.
• The sensor demonstrated distinct changes in capacitance, conductivity, and permittivity upon DNA hybridization.
• The sensor accurately differentiated between complementary, non-complementary, and mismatched DNA samples, validating its specificity.

Conclusions:

• The sub-20-nm gold electrode sensor offers a highly sensitive and specific method for identifying infectious Ganoderma species.
• This novel biosensor provides a rapid and efficient alternative to traditional diagnostic techniques for plant pathogens.
• The technology has potential applications in early disease detection and management of Ganoderma-related crop diseases.