Competition Between Protein and DNA for Binding to Natural Sepiolite Nanofibers

Area of Science:

• Materials Science
• Biotechnology
• Nanotechnology

Background:

• Sepiolite nanofibers, natural silicates, show potential as nanocarriers for biomolecule delivery.
• Their structure facilitates binding to various biomolecules like DNA and proteins through multiple interactions.
• Understanding competitive adsorption is key to optimizing nanocarrier function.

Purpose of the Study:

• To investigate the competitive adsorption of DNA and proteins onto sepiolite nanofibers.
• To elucidate the role of electrostatic interactions and calcium ions in the adsorption process.
• To assess the potential of sepiolite-based biohybrids for gene transfer applications.

Main Methods:

• Adsorption isotherms were used to measure protein binding efficiency (BSA and monoclonal antibody).
• Zeta potential measurements characterized surface charge properties.
• Competitive adsorption experiments analyzed the interplay between DNA and protein binding.

Main Results:

• Protein adsorption to sepiolite is charge-dependent and enhanced by CaCl2.
• Coating sepiolite with DNA reduced protein adsorption, an effect reversible by CaCl2.
• DNA binding efficiency decreased with protein pre-adsorption, with Ca2+ partially restoring it for BSA.

Conclusions:

• Electrostatic forces are primary drivers of protein adsorption onto sepiolite.
• Sepiolite-DNA and sepiolite-protein interactions are complex and influenced by ionic strength.
• Developed biohybrids offer a promising nanoplatform for gene delivery with potential clinical relevance.