Tailoring surface properties to build colloidal diagnostic devices: controlling interparticle associations

Area of Science:

• Materials Science
• Colloid Science
• Biotechnology

Background:

• Controlling particle surface properties is crucial for applications like combinatorial peptide synthesis.
• Fluorescent silica nanoparticles can act as reporters to encode synthesized peptides via interparticle association.

Purpose of the Study:

• To tailor the surface chemistry of sub-micrometer fluorescent silica reporters for robust adhesion to larger silica microparticles.
• To ensure these particle associations withstand harsh chemical and biological environments during peptide synthesis and screening.

Main Methods:

• Investigated interparticle association under various peptide synthesis solvents and biological buffers (PBS, MES, MES/EDC).
• Quantified remaining reporters after each step to assess adhesion stability.
• Utilized zeta potential and X-ray photoelectron spectroscopy to explore surface functionality and polyelectrolyte modification.

Main Results:

• Demonstrated that surface functionality and polyelectrolyte modification significantly influence reporter adhesion.
• Optimized conditions for robust interparticle association capable of withstanding demanding experimental procedures.
• Successfully quantified reporter retention, validating the engineered adhesion.

Conclusions:

• Surface engineering of fluorescent silica reporters is key to achieving stable colloidal association for encoded synthesis.
• The developed method provides a robust platform for combinatorial peptide library synthesis and screening.
• Understanding surface chemistry and polyelectrolyte effects is vital for optimizing reporter-particle interactions.