Rational Design of Peptide-Functionalized Surface Plasmon Resonance Sensor for Specific Detection of TNT Explosive

Area of Science:

• Biomolecular Engineering
• Analytical Chemistry
• Biosensor Technology

Background:

• Conventional methods for detecting 2,4,6-trinitrotoluene (TNT) often lack sensitivity and selectivity.
• Monoclonal antibodies and their derived peptides offer potential for targeted analyte detection.
• Surface plasmon resonance (SPR) is a label-free detection technique sensitive to binding events.

Purpose of the Study:

• To rationally design and select a peptide for specific 2,4,6-trinitrotoluene (TNT) detection.
• To develop a maleimide-functionalized surface plasmon resonance (SPR) sensor for TNT quantification.
• To evaluate the selectivity of the developed TNT-binding peptide against TNT analogues.

Main Methods:

• Antigen-docking simulation and screening were employed to identify candidate TNT-binding peptides from anti-TNT antibody complementarity-determining regions (CDRs).
• Candidate peptides (TNTHCDR1, TNTHCDR2, TNTHCDR3) were synthesized and evaluated using an SPR sensor with a 3-aminopropyltriethoxysilane (APTES) functionalized surface.
• The selected TNT-binding peptide was immobilized on a maleimide-functionalized sensor chip using N-γ-maleimidobutyryl-oxysuccinimide ester (GMBS).

Main Results:

• Peptide TNTHCDR3 was identified as the most effective TNT-binding peptide among the candidates.
• The TNTHCDR3-based SPR sensor demonstrated selective binding to TNT in the presence of five different TNT analogues.
• The direct detection of TNT using the APTES-GMBS-based SPR sensor chip showed promising results.

Conclusions:

• The rationally designed peptide TNTHCDR3 exhibits high specificity for 2,4,6-trinitrotoluene (TNT) detection.
• The developed maleimide-functionalized SPR sensor provides a sensitive and selective platform for direct TNT detection.
• This approach holds significant potential for practical applications in explosive detection and security.