Development of a Generic Bio-Interface for Immuno-Biodetection on an Oxide Surface Targeting Pathogen Bacteria

Area of Science:

• Biosensing and Bioengineering
• Materials Science
• Microbiology

Background:

• Increasing microbial contamination necessitates rapid, selective, and sensitive detection methods.
• Acoustic wave biosensors offer potential for meeting these detection criteria.
• Existing methods often lack selectivity, sensitivity, or cost-effectiveness.

Purpose of the Study:

• To develop a generic, antibody-based biointerface for detecting a wide range of pathogenic bacteria.
• To functionalize various surfaces, including fragile materials, using silane-oxide chemistry.
• To demonstrate the specificity and sensitivity of the developed biointerface for bacterial detection.

Main Methods:

• Utilized self-assembled monolayers (SAMs) of aminopropyltriethoxysilane (APTES) and phenylene diisothiocyanate (PDITC) for antibody grafting.
• Developed biointerfaces on titanium and lithium niobate surfaces using two APTES grafting routes (toluene/heat vs. chloroform/room temperature).
• Employed surface characterization techniques (FTIR-ATR, XPS, WCA) and static biodetection experiments.

Main Results:

• Achieved comparable APTES grafting efficiency on titanium using both toluene and chloroform routes.
• Demonstrated successful biointerface elaboration on fragile surfaces using a mild chloroform-based method.
• Achieved high specificity in detecting *L. monocytogenes* (98% vs. *E. coli*, 85% vs. *L. innocua*) in static conditions.

Conclusions:

• Successfully developed a versatile biointerface for pathogenic bacterial detection using APTES and PDITC.
• The developed method is transferable to various surfaces, including fragile materials, and offers a mild functionalization route.
• The biointerface exhibits high specificity and sensitivity, making it suitable for microbial contamination monitoring.