Engineering Host-Guest Interactions for Next-Generation Heparin Biosensors

Area of Science:

• Supramolecular Chemistry
• Biomedical Engineering
• Analytical Chemistry

Background:

• Heparin is a vital anticoagulant requiring neutralization for safe clinical use.
• Protamine sulfate (PS) is the current standard antidote but has limitations.
• Developing effective and safer heparin antagonists is crucial.

Purpose of the Study:

• To evaluate a novel polycationic pillar[6]arene macrocycle (P12+) as a heparin neutralizer.
• To compare P12+ efficacy and safety with protamine sulfate (PS).
• To develop a sensitive heparin detection method using P12+.

Main Methods:

• In vitro heparin neutralization assays in physiological media.
• MTT assays for cytotoxicity assessment.
• Dynamic light scattering for aggregate size analysis.
• Host-guest indicator displacement assays (IDA) for heparin detection (UV-vis and fluorescence).
• Molecular dynamics simulations.

Main Results:

• P12+ demonstrated comparable or superior heparin neutralization to PS.
• P12+ exhibited low toxicity, suggesting in vivo potential.
• P12+ formed smaller nanoscale complexes compared to PS-heparin aggregates.
• P12+ showed enhanced neutralization of low-molecular-weight heparin.
• A fluorescence-based IDA enabled sensitive heparin detection (0.11 U/mL).

Conclusions:

• P12+ is a promising candidate for heparin neutralization with improved properties over PS.
• P12+ offers potential for both therapeutic neutralization and sensitive diagnostic detection of heparin.
• The study highlights the utility of pillararene macrocycles in biomedical applications.