Sensing cell adhesion using polydiacetylene-containing peptide amphiphile fibres

Area of Science:

• Biomaterials Science
• Cell Biology
• Nanotechnology

Background:

• Cell adhesion is crucial for biological processes.
• Developing intuitive methods to detect cell binding is important for research and diagnostics.
• Polydiacetylene (PDA) materials exhibit unique chromic properties upon external stimuli.

Purpose of the Study:

• To design and synthesize polydiacetylene-containing peptide amphiphile fibers for sensing cell adhesion.
• To investigate the colorimetric response of these fibers to cell binding.
• To optimize the fiber composition for enhanced colorimetric sensing of cell adhesion.

Main Methods:

• Synthesis of diacetylene-containing peptide amphiphiles functionalized with the RGDS cell-binding motif.
• Mixing functionalized amphiphiles with non-functionalized spacer amphiphiles.
• UV-initiated polymerization of diacetylenes to form blue fibers.
• Inducing cell adhesion to the RGDS-functionalized fibers and observing color changes.

Main Results:

• The synthesized fibers exhibited a color change from blue to pink upon cell adhesion.
• The colorimetric response could be tuned by altering the C-terminal amino acid of the spacer amphiphile.
• An optimal RGDS density was determined, corresponding to a 6:1 ratio of non-RGDS to RGDS amphiphiles for the best colorimetric response.

Conclusions:

• Polydiacetylene-peptide amphiphile fibers provide an effective colorimetric platform for sensing cell adhesion.
• The sensitivity and specificity of the sensor can be modulated by adjusting fiber composition and functionalization.
• This approach offers a simple and intuitive method for quantifying cell binding events.