Strong and Selective Adsorption of Lysozyme on Graphene Oxide

Abstract

Biosensing methods and devices using graphene oxide (GO) have recently been explored for detection and quantification of specific biomolecules from body fluid samples, such as saliva, milk, urine, and serum. For a practical diagnostics application, any sensing system must show an absence of nonselective detection of abundant proteins in the fluid matrix. Because lysozyme is an abundant protein in these body fluids (e.g., around 21.4 and 7 μg/mL of lysozyme is found in human milk and saliva from healthy individuals, and more than 15 or even 100 μg/mL in patients suffering from leukemia, renal disease, and sarcoidosis), it may interfere with detections and quantification if it has strong interaction with GO. Therefore, one fundamental question that needs to be addressed before any development of GO based diagnostics method is how GO interacts with lysozyme. In this study, GO has demonstrated a strong interaction with lysozyme. This interaction is so strong that we are able to subsequently eliminate and separate lysozyme from aqueous solution onto the surface of GO. Furthermore, the strong electrostatic interaction also renders the selective adsorption of lysozyme on GO from a mixture of binary and ternary proteins. This selectivity is confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), fluorescence spectroscopy, and UV–vis absorption spectroscopy.

Insight into the Interaction of Graphene Oxide with Serum Proteins and the Impact of the Degree of Reduction and Concentration

“…18,25,[36][37] The results shown above demonstrated that the adsorbed proteins type varied according to the reduction degree and exposure concentration of GO/rGOs. It is relatively easy to understand the influence of reduction degree on adsorbed proteins type.…”

“…25 Undoubtedly, proteins adsorption will change the physicochemical properties of GO, like size and surface properties, and lead to loss of its functions. More seriously, this interaction may bring risks of capillary blockage resulted from the size increase.…”

The Synergy of Graphene Oxide and Polydopamine Assisted Immobilization of Lysozyme to Improve Antibacterial Properties

“…The GO immobilized on the PDA film was spread out, and some folds and small wrinkles were observed clearly. This was caused by the carboxyl on the edge of the rGO and part of the hydroxyl on its basal plane can interact with amino group and part of hydroxyl on PDA mentioned in fount part . In addition, the large specific surface area structure on PDA/rGO film could provide more immobilized sites to cLY compared with pure PDA surface.…”

Dihydrolipoic Acid Conjugated Carbon Dots Accelerate Human Insulin Fibrillation

“…With recent nanotechnological developments in nanomedicine and biomedical engineering, much attention is focused on understanding the interaction and toxicity of nanomaterials on cellular components, such as proteins, plasma membranes and DNA [6][7][8][9][10]. Quantum dots (QDs), a class of typical nanoparticles, have been extensively studied with proteins to explore their potential biomedical applications.…”