Sensors and Actuators B Chemical (SENSOR ACTUAT B-CHEM)

Publications in this journal

• Article: Synthesis, sensor activity and logic behavior of a highly water-soluble naphthalimide derivative

  N. Georgiev, I. Yaneva, A. Surleva, A. Asiri, V. Bojinov
  Sensors and Actuators B Chemical 07/2013; 184:54-63.
• Article: AC frequency-based electrical stimulation of hydrogel microactuators employing Parylene-N coated electrodes

  J. R. Saunders, W. Moussa
  [show abstract] [hide abstract]
  ABSTRACT: This article demonstrates the first AC-frequency based electrical actuation of hydrogels employing coplanar microelectrodes coated with Parylene-N. For the first time hydrogel microactuators were operated at applied voltages up to 40 Vpk-pk without any electrolyte electrolysis or external pumping equipment. An RC circuit model was developed to determine the characteristic frequency required to overcome electrostatic shielding, as the hydrogels were actuated in the polarizable potassium hydroxide (KOH). The characteristic actuation frequency was found to be between 10 kHz and 1 GHz, with the minimum frequency at an electrolyte concentration of 1 mM and Parylene-N thickness of 100 nm. This circuit model was also extended to calculate the total capacitance of the hydrogel-based system. To validate the circuit model, the total capacitance of the system was experimentally measured using capacitance and admittance spectroscopy, for Parylene-N thicknesses from 2145 ± 55 nm to 565 ± 7 nm and from 1 mM to 10 mM KOH. Good agreement was found at higher frequencies, while at lower frequencies the system demonstrated frequency and concentration dependent behavior. The spectroscopy results were used to calculate the apparent power of the system based off the maximum electric potential of 40 Vpk-pk applied during actuation, with an absolute minimum and maximum of ~2 × 10−4 V A and ~2 × 10−2 V A, respectively. To determine actuation dynamics systems were fabricated with Parylene-N thicknesses from 907 ± 28 nm to 348 ± 13 nm and equilibrated with 1 mM or 5 mM KOH, providing a system above and a system below the predicted characteristic frequency, respectively. The 1 mM KOH system displayed true strains from 18% to 30% with response times from 14.7 s to 4.7 s, with optimum response at applied electric fields of 16 kV/m or 40 Vpk-pk with an 80% duty cycle. The 5 mM KOH system had a maximum true strain of ~7% and response time of 14.9 s. The trend observed while increasing frequency was also observed when a 1 mM KOH sample was subjected to increasing applied electric potential, which showed a 674% increase in true strain and a 703% decrease in response time, from 15 Vpk-pk to 40 Vpk-pk. All systems actuated displayed deformation at all frequencies tested; thus even a minimal frequency can disturb electrostatic shielding, but above the characteristic frequency deformation and response times were optimum. This work overcomes the previous operational challenges associated with electrical hydrogel actuation, and investigates the electrical and actuation characteristics of the hydrogel-based system. Moreover, as hydrogels operated at lower frequencies still displayed actuation, hydrogel actuation could occur at low power zones enabling its integration within ultra-low power portable systems.
  Sensors and Actuators B Chemical 06/2013; 182:761-773.
• Article: Simple and multi-configurational flow-cell detector for UV-Vis spectroelectrochemical measurements in commercial instruments

  L. León, J. J. Maraver, J. Carbajo, J. D. Mozo
  Sensors and Actuators B Chemical 06/2013;
• Article: Morphology dependent ammonia sensing with 5-sulfosalicylic acid doped nanostructured polyaniline synthesized by several routes

  Krishanu Chatterjee, Palash Dhara, Saibal Ganguly, Kajari Kargupta, Dipali Banerjee
  [show abstract] [hide abstract]
  ABSTRACT: Polyaniline (PANI) doped with 5-sulfosalicylic acid (SSA) has been synthesized employing several techniques, viz. polymerization, Langmuir Blodgett (LB), spin-coating and electrodeposition. The influence of process variation on the structure, electrical conductivity and ammonia vapour sensing performance (response percentage and response time) has been investigated. The synthesized samples have been structurally characterized by transmission electron microscopy (TEM), UV–vis, and FTIR spectra. TEM analysis reveals formation of nanorods and nanospheres of PANI. Nanorods are formed for the samples synthesized by electrodeposition and LB technique whereas for the samples synthesized by polymerization and spin-coating, nanospheres are formed. Among these four different synthesized samples, the one deposited by LB technique exhibits highest conductivity due to the ordered molecular architecture. An exploration of variation of conductivity of these samples after exposure to ammonia reveals that the polymerized sample having highest surface to volume ratio exhibits fastest response (least response time), while the spin coated sample show sluggish response. The importance lies in the mapping between response percentages of different samples with the surface to volume ratio of the various nanostructures.
  Sensors and Actuators B Chemical 05/2013; 181:544-550.
• Article: Optical fibre long period grating sensor with a polyelectrolyte alternate thin film for gas sensing of amine odors

  Tao Wang, Sergiy Korposh, Stephen James, Ralph Tatam, Seung-Woo Lee
  [show abstract] [hide abstract]
  ABSTRACT: The formation of poly(acrylic acid) (PAA) and poly(allyamine hydrochloride) (PAH) multilayers on an optical fibre long period grating (LPG) by the layer-by-layer (LbL) assembly technique for highly sensitive ammonia gas detection is reported. Observation of the LPG's transmission spectrum indicated that the refractive index (RI) of the PAH/PAA alternate layer film was changed on exposure to ammonia, possibly via a change in the structure of the polyelectrolyte multilayers. PAA could act as a receptor for binding of amine compounds including ammonia, which would induce changes in the coating properties such as optical thickness (OT), film thickness/density and electrostatic interaction, thus influencing the transmission spectrum of the LPG. The ammonia binding is based on the acid-base interaction to free carboxylic acid groups of PAA. An LPG of period 100 μm with a 7-cycle PAH/PAA coating exposed to ammonia exhibited a limit of detection of 10.7 ppm. Film morphology and thickness changes due to the binding of ammonia gas, explaining the sensing mechanism, were confirmed through atomic force microscopic (AFM) measurements.
  Sensors and Actuators B Chemical 05/2013;
• Article: Carboxylated multiwalled carbon nanotubes based biosensor for aflatoxin detection

  Chandan Singh, Saurabh Srivastava, Md Azahar Ali, Tejendra K. Gupta, Gajjala Sumana, Anchal Srivastava, R.B. Mathur, Bansi D. Malhotra
  [show abstract] [hide abstract]
  ABSTRACT: We report results of studies relating to the development of an electrochemical immunosensor based on carboxylated multiwalled carbon nanotubes (c-MWCNTs) electrophoretically deposited onto indium tin oxide (ITO) glass. This c-MWCNTs/ITO electrode surface has been functionalized with monoclonal aflatoxin B1 antibodies (anti-AFB1) for the detection of aflatoxin-B1 using electrochemical technique. Electron microscopy, X-ray diffraction and Raman studies suggest the successful synthesis of c-MWCNTs and the Fourier transform infra-red spectroscopic (FT-IR) studies reveal its carboxylic functionalized nature. The proposed immunosensor shows high sensitivity (95.2 μA ng−1mL cm−2), improved detection limit (0.08 ng mL−1) in the linear detection range of 0.25-1.375 ng mL−1. The low value of association constant (0.0915 ng mL−1) indicates high affinity of immunoelectrode towards aflatoxin (AFB1).
  Sensors and Actuators B Chemical 04/2013;
• Article: Development of hard water sensor using Fluorescence Resonance Energy Transfer

  Dibyendu Dey, D. Bhattacharjee, S. Chakraborty, Syed Arshad Hussain
  [show abstract] [hide abstract]
  ABSTRACT: A method is presented for the sensing of water hardness by determining the concentration of calcium and magnesium in water, based on Fluorescence resonance energy transfer (FRET) process. The principle of the proposed sensor is based on the change of FRET efficiency between two laser dyes Acriflavine (Acf) and Rhodamine B (RhB) in presence of permanent hard water components (CaCl2 and MgCl2). Nanodimensional clay platelet laponite was used to enhance the efficiency of the sensor.
  Sensors and Actuators B Chemical 04/2013;
• Article: Green Synthesis of Silver Nanoparticles and Their Application for the Development of Optical Fiber Based Hydrogen Peroxide Sensor

  Chandrakant Tagad, Sreekantha Dugasani, Rohini Aiyer, Sungha Park, Atul Kulkarni, Sushma Sabharwal
  Sensors and Actuators B Chemical 04/2013;
• Article: Ce-doped ZnO nanorods for the detection of hazardous chemical

  G.N. Dar, Ahmad Umar, S.A. Zaidi, Ahmed A. Ibrahim, M. Abaker, S. Baskoutas, M.S. Al-Assiri
  [show abstract] [hide abstract]
  ABSTRACT: This paper reports a successful synthesis, characterizations and an efficient chemical sensor application of as-synthesized Ce-doped ZnO nanorods. The Ce-doped ZnO nanorods were synthesized by simple low-temperature hydrothermal process. The as-synthesized nanorods were characterized in terms of their morphological, structural and compositional properties. The morphological and structural studies revealed that the synthesized nanorods were grown in high-density and possessed well-crystallinity. The as-synthesized nanorods were used as an effective electron mediator for the fabrication of an efficient hydroquinone chemical sensor. The fabricated sensor exhibited high and reproducible sensitivity of ∼10.218 ± 0.01 mA cm−2 mM−1 and detection limit of ∼10 nM. To the best of our knowledge, this is the first ever report on the fabrication of hydroquinone chemical sensor using Ce-doped ZnO nanostructures. This work demonstrates that simply synthesized Ce-doped ZnO nanostructures can be used as an effective electron mediator for the fabrication of chemical sensors.
  Sensors and Actuators B Chemical 03/2013; 173:72–78.