Piezoelectric biosensors

The piezoelectric biosensor is a class of micro electromechanical systems (MEMS) based on the principle of measurement of changes in oscillating crystal resonance frequency due to bioreceptor and analyte interactions. In piezoelectric MEMS biosensors, the transducer is made of piezoelectric material (hke quartz) and the biosensing material is then coated on the piezoelectric material, which vibrates at the natural frequency. Piezoelectric materials have no center of symmetry and produce an electric signal when stressed mechanically (i.e., by applying some pressure on them). A crystal oscillates at a certain 

In the case of a piezoelectric crystal resonator, the traveling wave is either a bulk acoustic wave (BAW) propagating through the interior of the substrate or a surface acoustic wave (SAW) propagating on the surface of the substrate. There are two main types of piezoelectric sensors  

If the wave propagates through the substrate, the wave is called a bulk wave. The most commonly used BAW devices are the thickness shear mode (TSM) resonator and the shear-horizontal acoustic plate mode (SH-APM) sensor. The TSM, also widely referred to as a quartz crystal microbalance (QCM), is the best-known and simplest 

The piezoelectric transducer is suitable for DNA and protein detection with a detection limit of 1 ng cm (Nirschl et al., 2009). The piezoelectric sensor has been used in various applications such as cholera toxin diagnostic detection, hepatitis B, hepatitis C, and food-borne pathogen detection (Skladal et al., 2004 Serra et al., 2008 Chen et al., 2008). The piezoelectric transducer is a very sensitive method, noting that a detection limit of 

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J. Horacek and P. Skladal, Improved direct piezoelectric biosensors operating in liquid solution for the competitive label-free immunoassay of 2,4-dichlorophenoxyacetic acid. Anal. Chim. Acta 347, 43-50 (1997). 

Wu, T.Z. (1999) A piezoelectric biosensor as an olfactory receptor for odour detection electronic nose. Biosens. Bioelectron. 14 9-18. 

J.M. Abad, F. Pariente, L. Hernandez, H.D. Abruna and E. Lorenzo, Determination of organophosphorus and carbamate pesticides using a piezoelectric biosensor, Anal. Chem., 70 (1998) 2848-2855. 

After a short historical survey the fundamentals of signal transducers and the present state of thermometric, optoelectronic, and piezoelectric biosensors are presented. The most relevant electrochemical techniques are outlined in detail because electrochemical transducers are predominant. The aim of the second section is to provide information on the function of the biocomponents used in biosensors, primarily enzymes, but also antibodies and chemoreceptors. Special attention is paid to the methods of immobilization of the biomaterial and to the discussion and mathematical modeling of the interplay of biochemical reactions with mass transfer processes in immobilized enzyme electrodes. 

Key words Piezoelectric biosensors, QCM, Cholinesterase, Pesticides, Drugs, Antibody, Kinetic... 

However, piezoelectric biosensors also have a number of disadvantages ... 

Several piezoelectric sensors for the detection of low molecular weight compounds like pesticides (9-11), toxins (12), or drugs (13) have been reported in recent years (Table 1). A piezoelectric biosensor with a reversibly coupled (via His-tag) paraoxon for the binding of tetrameric butyrylcholinesterase to the active site of the enzyme has also been described by us (14). The commercially available devices have recently been reviewed (15, 16). 

Halamek, J., Pribyl, J., Makower, A., Skladal, P., and Scheller, F. W. (2005) Sensitive detection of organophosphates in river water by means of a piezoelectric biosensor. Analytical and Bioanalytical Chemistry 382,1904—1911... 

The use of aptamers as biorecognition element in piezoelectric biosensors will be here reported with particular application to the detection of thrombin. 

This chapter deals with the coupling of the thrombin aptamer with quartz crystal microbalance devices for the development of aptamer-based piezoelectric biosensors. 

Skladal, P., dos Santos Riccardi, C., Yamanaka, H., Inacio da Costa, P. (2004). Piezoelectric biosensors for real-time monitoring of hybridization and detection of hepatitis C virus. J. Virol. Methods 117, 145-151... 

Skladal, P., Jilkova, Z., Svoboda, I., and Kolar, V. (2006) Investigation of osteoprote-gerin interactions with ligands and antibodies using piezoelectric biosensors. Biosens. Bioelectron. 20,2027-2034... 

Horacek, J. and Skladal, P. (1998) Characterization of the interactions between immobilized parathion and the corresponding recombinant scFv antibody using a piezoelectric biosensor. Food Agric. Immunol. 10, 363-374... 

In Part I, we describe several mechanical detectors that modify their mechanical properties as a result of biological interactions. Such mechanical direct biosensors typically sense resonance of the mechanical element, which changes when the target molecule binds to the surface. Piezoelectric biosensors (see Chaps. 1-3) employ a technology that is widely used in a variety of applications (e.g., vapor deposition of metals) and is thus readily available and relatively inexpensive. Cantilever-based systems (see Chaps. 4 and 5) can be miniaturized to micrometer dimensions with attendant benefits for system and sample size. 

New Frontiers in Nucleic Acid-Based Piezoelectric Biosensors ... 

The development of a DNA piezoelectric biosensor for the detection of the mecA gene, present in methicillin resistant Staphylococcus aureus (MRSA) strain, was described [6]. Methicillin resistant Staphylococcus aureus is the... 

Davis K A and Leary T R 1989 Continuous liquid phase piezoelectric biosensor for kinetic immunoassays Anal. Chem. 61 1227... 

Nevertheless, the use of antibodies as immobilized affinants is the most common way to obtain piezoelectric biosensors [236]. To overcome the problems due to solvent adsorption. 

A piezoelectric biosensor system was applied for the detection of E. coli using an antibody coating (113). The frequency shifts correlated with an E. coli concentration in the range of 10 - 10 cells.cm for a reaction time of 30 min. The frequency shift was... 

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