Piezoelectric microgravimetry

The method of piezoelectric microgravimetry (nanogravimetry) at an EQCM can be considered as a novel and highly sensitive version of -> electrogravimetry. 

Piezoelectric microgravimetry in conjimction with electrochemical measurements is a very powerful but relatively simple and cheap techrrique, and so within the last twenty years it has become one of the most popular hyphenated techrriques for studying the formation of conducting polymer films and ion and solvent exchange processes that occur during their redox reactions, which provide valtrable information about the reaction mechanism [6-9,43,70,89,90,98,107,151,153,154,156-166,168-232],... 

The application of combined electrochemical and nonelectrochemical techniques, such as piezoelectric microgravimetry atEQCM [10,40,73,74,132,134,139-144], radiotracing [27,145], various spectroscopies [16,44,72,100,116,117,146] and microscopies [19,29,46,79,97,114,127,147,148], ellipsometry [15,21,26,86], conductivity [80], and probe beam deflection [149], has allowed irs to gain very detailed insights into the nature of electropolymerization and deposition processes, and so the production of conducting polymers, polymeric films, and composites with desired properties is now a well-established area of the electrochemical and material sciences. 

Radiotracer technique [62, 77, 80, 84] is well suited to the investigation of the motion of counterions and coions coupled to the electron-transfer and transport processes, and offers the opportunity of studying the attainment of equilibrium and steady states in regard to the sorbed ions at any potential that is at any ratio of oxidized and reduced sites in the film, without disturbing the original experimental conditions. Piezoelectric microgravimetry at... 

E., and Kutner, W. (1997) Simultaneous photoelectro chemistry and piezoelectric microgravimetry, with the use of electrochemical quartz crystal microbalance, of surface layers formed at the Cu/Cu(II), P-alanine interface. Electrochim. Acta, 42 (19), 2935-2941. 

Dopamine might be a pharmaceutical for which the highest number of MIP based sensors have been constructed. Voltammetry [361,413] and its derivative techniques like differential pulse voltammetry [347,395,418], differential pulse anodic and cathodic stripping voltammetries [353,387,415] ion selective electrodes [372], as swell as piezoelectric microgravimetry [401] and thermogravimetry [427] are among the mechanisms used for the detection in dopamine selective MIP based sensors. 

A. Pietrzyk et al. reported an imprinted poly[bis(2,2 -bithienyl)methane] film for a piezoelectric microgravimetry of dopamine. The MIP film contained either a 3,4-dihydroxyphenyl or benzo-18-crown-6 substituent, for selective determination of dopamine and was electropolymerized on an imderlayer of poly(bithiophene) on a Pt/ quartz resonator. The detection limit of the method was reported to be 10 nM [401]. Kan et al, on the other hand, developed a composite of multiwalled carbon nanotube (MWCNTs) and MIP with dopamine templates using the copolymerization reaction of methacrylic acid and trimethylolpropane trimethacrylate (copoly(MAA-co-TRIM)) on the vinyl functionalized MWCNT surface and used the composite for the thermo-gravimetric analysis of the template. The composite was found to be selective towards dopamine in comparison with epinephrine and the response was linear in the range of 5.0 X 10 "-2.0 X 10 M [427]. 

A. Pietrzyk, S. Suriyanarayanan, W. Kutner, E. Mahgaspe, M.E. Zandler and F. D Souza, Molecularly imprinted poly[bis(2,2 -bithienyl)methane] film with built-in molecular recognition sites for a piezoelectric microgravimetry chemosensor for selective determination of dopamine. Bioelectrochemistry, 80 (1) 62-72,2010. 

Noworyta K, Kutner W, Wijesinghe CA, Srour SG, D Souza F (2012) Nicotine, cotinine, and myosmine determination using polymer films of tailor-designed zinc porphyrins as recognition units for piezoelectric microgravimetry chemosensors. Anal Chem 84 2154—2163... 

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