Simultaneous anomalous reflection and quartz-crystal microbalance measurements of protein bindings on a gold surface

Abstract

Protein bindings onto a gold surface were detected simultaneously by QCM (delta F(water)) and anomalous reflection (deltaR) of gold on the same surface in aqueous solutions; the obtained delta F(water)/deltaR values correlated with surface areas and viscosity of proteins.

A new imaging method for gold-surface adsorbates based on anomalous reflection

“…For instance, a gold electrode of the quartz microbalance can be used as the AR platform, without making any grating structure at the electrode surface for the SPR measurements [37]. AR-QCM dual measurements have been performed to estimate the amount of water molecules binding to protein [38]. In addition, AR provides a high spatial resolution, of the order of micrometers or less, because the illumination energy scarcely propagates along the surface.…”

Surface Modification Enhanced Reflection Intensity of Quartz Crystal Microbalance Sensors upon Molecular Adsorption

“…Particularly, a reflection-based system, utilizing light reflection perpendicular to the sensing surface, has a less complex setup compared to other optical systems and allows for the simultaneous detection of biomolecules. 17 However, current reflection-based systems show low sensitivity compared to the QCM system and hinder further characterization of the adsorption events. The sensitivity should be improved to quantitatively detect and analyze surface phenomena.…”

Sensitive Detection of Small Molecule–Protein Interactions on a Metal–Insulator–Metal Label‐Free Biosensing Platform

“…Early examples of AR‐based technology include its use for analyzing biotin–avidin interactions,12 interactions between calmodulin and synthetic α‐helical peptides,13a and interactions between synthetic peptides and proteins displayed on T7 phage surfaces in solution13b that were accomplished by Kajikawa, Mihara and coworkers. Okahata and colleagues have demonstrated the feasibility of protein‐binding assays based on a combination of the AR method with a quartz crystal microbalance (QCM) 14. More recently, Kajikawa’s group presented an exciting AR biochip for avidin detection 15.…”

“…Okahata and colleagues have demonstrated the feasibility of protein-binding assays based on a combination of the AR method with a quartz crystal microbalance (QCM). [14] More recently, Kajikawas group presented an exciting AR biochip for avidin detection. [15] However, AR-based array technology has to be developed to a point where it can be used to detect proteinprotein interactions in a multiplexed format (e.g., a microarray).…”