Ultrasensitive detection of endotoxins using computationally designed nanoMIPs

Area of Science:

• Biomaterials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Endotoxins, particularly from Escherichia coli, pose significant health risks.
• Accurate and sensitive detection of endotoxins is crucial for clinical diagnostics and public health.
• Existing detection methods may lack the required sensitivity, selectivity, or cost-effectiveness.

Purpose of the Study:

• To design and synthesize novel molecularly imprinted polymer nanoparticles (nanoMIPs) for the specific recognition and detection of endotoxins.
• To utilize computational modeling for optimizing the selection of functional monomers for enhanced binding affinity.
• To develop a highly sensitive and selective endotoxin detection platform using surface plasmon resonance (SPR) biosensors.

Main Methods:

• Computational modeling was employed to screen 21 monomers based on binding energy with endotoxin.
• Functional monomers (itaconic acid, methacrylic acid, acrylamide) were selected for nanoMIP synthesis via solid-phase photopolymerization.
• NanoMIPs were characterized for size (200-235 nm) and surface functional groups for sensor immobilization.
• A novel triethylamine method enhanced gold nanoparticle functionalization for improved endotoxin capture.
• Surface Plasmon Resonance (SPR) biosensing was used to evaluate the affinity and selectivity of the nanoMIPs.

Main Results:

• Selected nanoMIPs demonstrated strong binding affinity and selectivity for endotoxin.
• The nanoMIPs exhibited dissociation constant (KD) values in the range of 4.4-5.3 × 10⁻¹⁰ M.
• An ultrasensitive limit of detection of 0.44 ± 0.02 ng mL⁻¹ was achieved using itaconic acid-based nanoMIPs.
• The nanoMIP sensor surface demonstrated high reusability, with >30 regeneration cycles without significant loss of binding activity.
• The triethylamine method significantly improved endotoxin sample preparation and sensor response.

Conclusions:

• The study successfully developed computationally designed nanoMIPs for ultrasensitive endotoxin detection.
• The combination of molecular modeling, optimized synthesis, and SPR biosensing offers a robust platform for endotoxin analysis.
• The developed nanoMIPs exhibit high affinity, selectivity, and reusability, presenting a cost-effective solution for endotoxin monitoring.
• This approach holds significant potential for applications in clinical diagnostics and ensuring the safety of pharmaceutical products.