Nanobiosensors exploiting specific interactions between an enzyme and herbicides in atomic force spectroscopy

Area of Science:

• Nanotechnology
• Biochemistry
• Analytical Chemistry

Background:

• Increasing agrochemical use necessitates sensitive detection methods.
• Atomic Force Microscopy (AFM) offers high sensitivity at the nanoscale.
• Nanosensors can enhance detection capabilities for environmental contaminants.

Purpose of the Study:

• To develop and validate a nanobiosensor for detecting specific herbicides.
• To exploit enzyme-functionalized AFM tips for enhanced biorecognition.
• To quantify the specific enzyme-herbicide interaction forces.

Main Methods:

• Functionalization of AFM tips with acetolactate synthase (ALS) enzyme.
• Utilizing Atomic Force Spectroscopy (AFS) to measure tip-substrate adhesion forces.
• Applying the Johnson-Kendall-Roberts (JKR) model to estimate specific forces.

Main Results:

• ALS-functionalized AFM tips (nanobiosensors) showed significantly increased adhesion forces.
• Metsulfuron-methyl and imazaquin detection resulted in approximately 250% and 160% force increases, respectively.
• Specific biorecognition force was identified as crucial for enhanced nanobiosensor sensitivity.

Conclusions:

• Engineered nanobiosensors provide a highly sensitive platform for herbicide detection.
• The developed method demonstrates potential for detecting various analytes via specific biorecognition.
• This approach paves the way for novel nanosensor designs in environmental monitoring.