Control of protein structure and function through surface recognition by tailored nanoparticle scaffolds

Area of Science:

• Nanotechnology
• Biochemistry
• Surface Chemistry

Background:

• Oligo(ethylene glycol) (OEG) ligands are crucial for nanoparticle functionalization.
• Surface recognition and controlled interactions are key in biosensing and drug delivery.

Purpose of the Study:

• To fabricate water-soluble cadmium selenide (CdSe) nanoparticle scaffolds.
• To achieve surface recognition of chymotrypsin (ChT) using functionalized nanoparticle scaffolds.
• To investigate different levels of interaction and their reversibility.

Main Methods:

• Synthesis of thioalkyl and thioalkylated OEG ligands with varied chain-end functionalities.
• Fabrication of water-soluble CdSe nanoparticle scaffolds using these ligands.
• Demonstration of surface recognition and interaction with chymotrypsin (ChT).

Main Results:

• Three distinct interaction levels with ChT were achieved based on ligand termination: no interaction, inhibition with denaturation, and reversible inhibition with structural retention.
• Carboxylate-terminated OEG ligands enabled reversible ChT inhibition, with activity restored by increasing ionic strength.
• Hydroxyl-terminated OEG showed no interaction, while carboxylate-terminated thioalkyl ligands caused inhibition with denaturation.

Conclusions:

• Functionalized nanoparticle scaffolds can precisely control enzyme interactions.
• Ligand design is critical for achieving specific binding, inhibition, and reversible modulation of enzyme activity.
• This platform offers potential for developing advanced biosensors and controlled enzyme delivery systems.