Jump to main content
Jump to site search

Issue 13, 2015
Previous Article Next Article

Surface charge effects in protein adsorption on nanodiamonds

Author affiliations

Abstract

Understanding the interaction of proteins with charged diamond nanoparticles is of fundamental importance for diverse biomedical applications. Here we present a thorough study of protein binding, adsorption kinetics and structure on strongly positively (hydrogen-terminated) and negatively (oxygen-terminated) charged nanodiamond particles using a quartz crystal microbalance by dissipation and infrared spectroscopy. By using two model proteins (bovine serum albumin and lysozyme) of different properties (charge, molecular weight and rigidity), the main driving mechanism responsible for the protein binding to the charged nanoparticles was identified. Electrostatic interactions were found to dominate the protein adsorption dynamics, attachment and conformation. We developed a simple electrostatic model that can qualitatively explain the observed adsorption behaviour based on charge-induced pH modifications near the charged nanoparticle surfaces. Under neutral conditions, the local pH around the positively and negatively charged nanodiamonds becomes very high (11–12) and low (1–3) respectively, which has a profound impact on the protein charge, hydration and affinity to the nanodiamonds. Small proteins (lysozyme) were found to form multilayers with significant conformational changes to screen the surface charge, while larger proteins (albumin) formed monolayers with minor conformational changes. The findings of this study provide a step forward toward understanding and eventually predicting nanoparticle interactions with biofluids.

Graphical abstract: Surface charge effects in protein adsorption on nanodiamonds

Back to tab navigation

Supplementary files

Publication details

The article was received on 13 Jan 2015, accepted on 16 Feb 2015 and first published on 19 Feb 2015


Article type: Paper
DOI: 10.1039/C5NR00250H
Author version
available:
Download author version (PDF)
Citation: Nanoscale, 2015,7, 5726-5736

  •   Request permissions

    Surface charge effects in protein adsorption on nanodiamonds

    M. Aramesh, O. Shimoni, K. Ostrikov, S. Prawer and J. Cervenka, Nanoscale, 2015, 7, 5726
    DOI: 10.1039/C5NR00250H

Search articles by author

Spotlight

Advertisements