Final Workshop: “Biosensors: applications and potential for bioactive compound screening”

Faro (Portugal), 20-21st February 2018.

Quartz Crystal Microbalance Biosensors Basic Principles and Applications

Abstract:

 

Rui M. Borges dos Santos (rmsantos@ualg.pt)

CCMAR


 

A biosensor is “a self-contained integrated device that provides quantitative analytical information using a biological recognition element retained in direct contact with a physical transduction element” [1]. Starting from this very broad definition, a brief overview of the currently available technologies and possible applications will be given, before focusing on one of the most widely used and probably the most versatile biosensor platform, the quartz crystal microbalance (QCM) [2].


The instrumental setup and experimental protocol of QCM, as applied to the study of biomolecular interactions, will be described, highlighting the advantages of in-house approaches (both in instrumental development and biosensor functionalization).


Recent advances on QCM signal analysis, such as impedance spectroscopy, allow obtaining additional information important to dissect the various processes potentially at play during molecular interactions [3], which we will exemplify using our recent results on the study of the hormone binding protein transthyretin.


Finally, the importance of the complete thermodynamic characterization of biomolecular interactions, which can only be obtained with calorimetric methods like Isothermal Titration Calorimetry (ITC is considered the gold-standard technique in such studies) will be explained [4]. ITC however as some evident drawbacks, especially when used in a high-throughput setting such as in rational drug-design [5]. A new in-house prototype, combining a calorimeter with a QCM to address the ITC shortcomings using the previously explained advantages of a biosensor, will be described.

 

References
[1] D. R. Thévenot et al., Pure Appl. Chem. 1999, 71, 2333.
[2] M. Pohanka, Int. J. Electrochem. Sci. 2017, 12, 496.
[3] J. M. Encarnação et al., J. Mol. Recognit. 2009, 22, 129.
[4] E. Freire, Drug Discov. Today 2008, 13, 869.
[5] N. C. Garbett, J. B. Chaires, Expert Opin. Drug Discov. 2012, 7, 299.

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