Molecular Sensors and Sensor Arrays Based on Polyaniline Microtubules
ABSTRACT This paper describes the fabrication of microtubular biosensors and sensor arrays based on polyaniline with superior transducing ability. These sensors have been tested for the estimation of glucose, urea, and triglycerides. As compared to that of a macro sensor, the response of the microtubular sensor for glucose is higher by a factor of more than 10(3). Isoporous polycarbonate membranes have been used to fabricate inexpensive devices by simple thermal evaporation of gold using appropriate machined masks. Polyaniline deposition and enzyme immobilization have been done electrochemically. Electrochemical potential control has been used to direct enzyme immobilization to the chosen membrane device and avoid cross talk with adjacent devices. This has enabled the immobilization of a set of three different enzymes on three closely spaced devices, resulting in a microtubule array that can analyze a sample containing a mixture of glucose, urea, and triglycerides in a single measurement. This, in essence, is an "electronic tongue".
- SourceAvailable from: Mohammad A Jafar Mazumder
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- "Polyaniline was electrodeposited on a platinum electrode coated with microporous polyacrylonitrile film  from the solution of aniline and GOD in buffer to immobilized GOD during polymerization process. In another report, Sukeerthi et al.  used a gold electrode covered with isoporous polycarbonate and deposited GOD during electro polymerization of aniline from the solution of aniline and GOD in buffer. They also immobilized Lipase and Urease by the adsorption method onto the same electrode surface, and this biosensor was able to detect glucose, urea and triolein in a single measurement from the mixture of these three. "
ABSTRACT: Electrically conducting polymers (ECPs) are finding applications in various fields of science owing to their fascinating characteristic properties such as binding molecules, tuning their properties, direct communication to produce a range of analytical signals and new analytical applications. Polyaniline (PANI) is one such ECP that has been extensively used and investigated over the last decade for direct electron transfer leading towards fabrication of mediator-less biosensors. In this review article, significant attention has been paid to the various polymerization techniques of polyaniline as a transducer material, and their use in enzymes/biomolecules immobilization methods to study their bio-catalytic properties as a biosensor for potential biomedical applications.Advanced Materials Research 08/2013; 810:173-216. DOI:10.4028/www.scientific.net/AMR.810.173
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- "parameters such as urea, glucose, and triglycerides and for the diagnosis of several diseases by nonspecific analysis of biological liquids have been deployed (Ciosek et al., 2008; Mottram et al., 2007; Sangodkar et al., 1996; Sohn et al., 2005; Sukeerthi and Contractor, 1999; Wang et al., 2007). Another considerable employment sector is that of environmental analyses, particularly in relation to the detection of heavy metal traces and various organic contaminants in water, such as pesticides and residuals from industrial plants (Aoki et al., 2009; Calvo et al., 2008; Carvalho et al., 2007; Constantino et al., 2004; Cortina et al., 2006; Di Natale et al., 1997; Gutes et al., 2005; Gutierrez et al., 2008; Hu et al., 2008; Ipatov et al., 2008; Kulapina and Mikhaleva, 2005; Makarova and Kulapina, 2009; Martinez-Manez et al., 2005; Men et al., 2004, 2005; Mikhaleva and Kulapina, 2006; Mourzina et al., 2001; Olsson et al., 2008; Turek et al., 2009; Valdes-Ramirez et al., 2009). "
ABSTRACT: The last years showed a significant trend toward the exploitation of rapid and economic analytical devices able to provide multiple information about samples. Among these, the so-called artificial tongues represent effective tools which allow a global sample characterization comparable to a fingerprint. Born as taste sensors for food evaluation, such devices proved to be useful for a wider number of purposes. In this review, a critical overview of artificial tongue applications over the last decade is outlined. In particular, the focus is centered on the chemometric techniques, which allow the extraction of valuable information from nonspecific data. The basic steps of signal processing and pattern recognition are discussed and the principal chemometric techniques are described in detail, highlighting benefits and drawbacks of each one. Furthermore, some novel methods recently introduced and particularly suitable for artificial tongue data are presented.Advances in food and nutrition research 01/2010; 61:57-117. DOI:10.1016/B978-0-12-374468-5.00002-7
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- "Thus, one may prepare multilayer Wlms of the CNTs and PANI alternately on a glassy carbon (GC) by using the layerby-layer method. Encouraged by the success of research in CNTs and PANI polymers  , we tried to assemble homogeneous and stable multiwalled carbon nanotubes (MWNTs) and PANI multilayer Wlms on GC electrodes using the layer-by-layer methodology. The conducting polymer Wlm was prepared from electrochemical polymerization of aniline. "
ABSTRACT: Conducting polymer film was prepared by electrochemical polymerization of aniline. Multiwalled carbon nanotubes (MWNTs) were treated with a mixture of concentrated sulfuric and nitric acid to introduce carboxylic acid groups to the nanotubes. By using the layer-by-layer method, homogeneous and stable MWNTs and polyaniline (PANI) multilayer films were alternately assembled on glassy carbon (GC) electrodes. Conducting polymer of PANI had three main functions: (i) excellent antiinterference ability, (ii) protection ability in favor of increasing the amount of the MWNTs immobilized on GC electrodes, and (iii) superior transducing ability. The protection effect of PANI film and the electrostatic interaction between positively charged PANI and negatively charged MWNTs both attributed to immobilizing abundant MWNTs stably, thereby enhancing the catalytic activity. The layer-by-layer assembled MWNTs and PANI-modified GC electrodes offered a significant decrease in the overvoltage for the H2O2 and were shown to be excellent amperometric sensors for H2O2 from +0.2V over a wide range of concentrations. As an application example, by linking choline oxidase (CHOD), an amplified biosensor toward choline was prepared. The choline biosensor exhibited a linear response range of 1x10(-6) to 2x10(-3) M with a correlation coefficient of 0.997, and the response time and detection limit (S/N=3) were determined to be 3 s and 0.3 microM, respectively. The antiinterference biosensor displays a rapid response and an expanded linear response range as well as excellent reproducibility and stability.Analytical Biochemistry 10/2005; 344(1):108-14. DOI:10.1016/j.ab.2005.06.007 · 2.22 Impact Factor