Manorama Singh

Polyaniline/polyacrylic acid/ multi-walled carbon nanotube modified electrodes for sensing ascorbic acid

A multi-walled carbon nanotube composite electrode incorporating Polyaniline (PANI) and Polyacrylic acid (PAA) is presented by diffusing aniline and PAA into Nafion- MWCNTs membranes supported upon a platinum macrodisc electrode. Nafion is found to be an ideal medium for dispersion of MWCNTs and for the formation of a homogeneous composite. The composite has been characterized utilizing SEM, TEM, FT-IR and electrochemical techniques. Electrochemical characterization reveals that the redox activity of the composite is improved with the cumulative effect of MWCNTs and PAA as additives. The electroanalytical behavior of the composite is evaluated towards the sensing of ascorbic acid in the presence of dopamine and uric acid exhibiting a detection limit of 2.5 × 10−7 M.

An insight review on the application of polymer-carbon nanotubes based composite material in sensor technology

Carbon nanotubes (CNT) polymer composites have shown potential applications for sensor/biosensor fabrication. Methods for preparation, characteristics are highlighted and future aspects are explored. Various analytes and polymeric materials have been cited to prove the importance of polymer/CNT composite systems in sensor technology.

Modification of Anthraquinone-2-Carboxylic Acid with Multiwalled Carbon Nanotubes and Electrocatalytic Behavior of Prepared Nanocomposite Towards Oxygen Reduction

We herein report a simple method for the preparation of multiwalled carbon nanotubes-anthraquinone-2-carboxylic acid (AQ-COOH-AMWCNTs) nano-composite. For the preparation of the composite, multiwalled carbon nanotubes have been functionalized with amino group (AMWCNTs) using 3-aminopropyltrimetho-xysilane. Then, anthraquinone-2-carboxylic acid is coupled to amino functionalized multiwalled carbon nanotubes (AMWCNTs) by carbodiimide coupling. Characterization of the material has been performed with scanning electron microscopy (SEM), transmission electron microscopy (TEM), fourier transform IR (FTIR) and cyclic voltammetry (CV). The prepared material exhibited electrocatalytic behavior towards the reduction of oxygen to hydrogen peroxide with a detection limit of 0.02 ppm. The prepared material was stable with no leaching observed of the mediator.

Evaluation of hearing in neonates and infants

Hearinge valuation of sixtyfour neonates and infants selected randomly from the outpatient departments of E. N. T., Paediatrics and Obstetrics wards was done by behavioral observation audiometry (BOA), tympanometry, acoustic reflex and auditory brainstem evoked response audiometry (ABR) in selected cases. A good correlation was found between BOA and ABR. Tympanometry and acoustic reflex measurements were not found to be useful for evaluating hearing status in infants and neonates. It was finally recommended that BOA should be used for screening hearing in infants and neonates. Cases who fail in BOA should be subjected to ABR for establishing true threshold of hearing.