title: Molecularly imprinted polymer (MIP) based piezoelectric microgravimetry chemosensor for selective determination of adenine.
abstract: An adenine-templated molecularly imprinted polymer (MIP) film, deposited on a poly(bithiophene) barrier film, served as the recognition element of a piezomicrogravimetric (acoustic) chemosensor. A 10MHz AT-cut shear-thickness-mode bulk-acoustic-wave quartz crystal resonator with Pt film electrodes was used as the signal transducer. Adenine electrooxidation was prevented by the barrier film. The MIP film was deposited by electrochemical co-polymerization of two functional monomers of bis(bithiophene) derivatives, bearing either the 18-crown-6 or dioxaborinane substituent, in the presence of the adenine template. A strong base solution was then used to extract the template. Completeness of the template removal was substantiated by the UV-vis, XPS, DPV, and EIS measurements. The chemosensor performance was evaluated with the piezoelectric microgravimetry detection at QCM under FIA conditions using a carrier acetonitrile-water (1:1, v:v) mixed solvent solution. The linear dynamic concentration range extended from at least 0.1 to 1mM for the 35 microL/min flow rate, and 100 microL volume of the injected adenine solution. The chemosensor selectivity allowed for discrimination of the adenine analyte from structurally and functionally related interferants, such as 2-aminopurine, guanine, and ascorbic acid. The determined from the FIA kinetic studies stability constant of the MIP-adenine complex, (18+/-2.4)x10(4)M(-1), was much higher than that of the MIP-(2-aminopurine), (650+/-90)M(-1), MIP-guanine, (122+/-11)M(-1), and MIP-(ascorbic acid), (92+/-10)M(-1), complexes. The concentration limit of detection was as low as 5 nM adenine for the 35 microL/min flow rate, and 1 mL volume of the injected sample solution.
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Pietrzyk
authors.forename: Subramanian
authors.initials: S
authors.lastname: Suriyanarayanan
authors.forename: Wlodzimierz
authors.initials: W
authors.lastname: Kutner
authors.forename: Raghu
authors.initials: R
authors.lastname: Chitta
authors.forename: Melvin E
authors.initials: ME
authors.lastname: Zandler
authors.forename: Francis
authors.initials: F
authors.lastname: D'Souza
mesh_terms: D000162:Acoustics / Q000295:instrumentation*; D000225:Adenine / Q000032:analysis*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D011108:Polymers / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013499:Surface Properties
chemical_list: D011108:Polymers; D000225:Adenine