Conducting Polymers in Sensor Design

Conducting polymers (CPs) as well as conducting polymer nanoparticles seem to be very applicable for the development of various analyte-recognizing elements of sensors and biosensors. This chapter reviews mainly fabrication methods as well as application of conducting polymers in sensors. Conducting polymers (CPs) have been applied in the design of catalytic and affinity biosensors as immobilization matrixes, signal transduction systems, and even analyte-recognizing components. Various types of conducting and electrochemically generated polymer-based electrochemical sensors were developed including amperometric catalytic and potentiodynamic affinity sensors. A very specific interaction of analyte with immobilized biological element results in the formation of reaction products

Conducting Polymers as Elements of Miniature Biocompatible Sensor

Conducting polymers (CPs), the so-called “fourth generation of polymeric materials”, can solve essential problems in biosensing technologies due to their unique material properties and implementation in innovative device systems. CPs have excellent biocompatibility. They can provide advantageous interfaces for bioelectrodes owing to their hybrid conducting mechanics, combining both electron and ionic charge carriers. Many (i.e. glucose) biosensors use immobilized enzymes to form a selective layer on CP structure. Miniaturization of sensors is a new requirement. Mini sensors are portable and wearable with low utilization of sample and cost-effective technology of production

Electrochemical and Optical Biosensors in Medical Applications

Analysis of many biochemical processes is of great significance for clinical, biological, food, environmental as well as bioterror applications. But, exchanging of the biochemical information to kind of electronic signal is a defiance due to connecting an electronic tool directly to a biological surrounding. Electrochemical detection instrument due to its advantageous to analyze the subject of a biological sample has a great potential in conversion of a biochemical occurrence to an electronic signal

Comparative Study of Alternating Low-band-Gap Benzothiadiazole Co-oligomers

The benzothiadiazole – arylene alternating conjugated oligomers have been designed and synthesized via Suzuki coupling reaction. The structures and properties of the conjugated oligomers were characterized by 1HNMR, 13CNMR, UV–vis absorption spectroscopy, photoluminescence (PL) spectroscopy. The luminescent measurements demonstrate that polybenzothiadiazoles are good chromophores able to form thin films by Langmuir-Blodgett (LB) technique, making them suitable for further applications. Also the electrical properties of obtained films confirm the good potential of these novel aryl-based π-conjugated polymers for the development of various electrical and electrochemical solid-state devices

Phenoxazine Based Units- Synthesis, Photophysics and Electrochemistry

A few new phenoxazine-based conjugated monomers were synthesized, characterized, and successfully used as semiconducting materials. The phenoxazine-based oligomers have low ionization potentials or high-lying HOMO levels (~4.7 eV), which were estimated from cyclic voltammetry. Conjugated oligomers offer good film—forming, mechanical and optical properties connected with their wide application. These results demonstrate that phenoxazine-based conjugated mers are a promising type of semiconducting and luminescent structures able to be used as thin films in organic electronics

Biocatalysts Immobilized in Ultrathin Ordered Films

The immobilization of enzymes and other proteins into ordered thin materials has attracted considerable attention over the past few years. This research has demonstrated that biomolecules immobilized in different [Langmuir-Blodgett (LB)/Langmuir-Schaefer (LS)] matrixes retain their functional characteristics to a large extent. These new materials are of interest for applications as biosensors and biocatalysts. We review the growing field of oxidases immobilized onto ordered Langmiur-Blodgett and Langmuir-Schaefer films. Strategies for the preparation of solid supports and the essential properties of the resulting materials with respect to the envisaged applications are presented. Basic effects of the nature of the adsorption and various aspects of the application of these materials as biosensors, biocatalysts are discussed. Outlook of potential applications and further challenges are also provided

Structure and Sensor Properties of Thin Ordered Solid Films

Miniaturized gas sensors and biosensors based on nanostructured sensing elements have attracted considerable interest because these nanostructured materials can be used to significantly improve sensor sensitivity and the response time. We report here on a generic, reversible sensing platform based on hybrid nanofilms. Thin ordered Langmuir-Blodgett (LB) films built of fluorene derivatives were used as effective gas sensors for both oxidative and reductive analytes. A novel immobilization method based on thin LB films as a matrix has been developed for construction of sensing protein layers. Biomolecules can often be incorporated into and immobilized on Langmuir-Blodgett films using adsorption methods or by covalent immobilization of proteins. The sensor sensitisation was achieved by an amphiphilic N-alkyl-bis(thiophene)arylenes admixed into the film. The interlaced derivative was expected to facilitate the electron transfer, thereby enhancing the sensor sensitivity. The results suggest that this may be very promising approach for exploring the interactions between proteins and high throughput detection of phenol derivatives in wastewater