An efficient nongassing electro-osmotic pump (EOP) with long-lasting electrodes and exceptionally stable operation is developed by using novel flow-through polyaniline (PANI)-wrapped aminated graphene (NH2-G) electrodes. The NH2-G/PANI electrode combines the excellent oxidation/reduction capacity of PANI with the exceptional conductivity and inertness of NH2-G. The flow rate varies linearly with voltage but is highly dependent on the electrode composition. The flow rates at a potential of 5 V for pristine NH2-G and PANI electrodes are 71 and 100 μL min(-1) cm(-2), respectively, which increase substantially by the use of NH2-G/PANI electrode. It increased from 125 to 182 μL min(-1) cm(-2) as the fraction of aniline increased from 66.63 to 90.90%. The maximum flux obtained is 40 μL min(-1) V(-1) cm(-2) with NH2-G/PANI-90.9 electrodes. The assembled EOP remained exceptionally stable until the electrode columbic capacity was fully utilized. The prototype shown here delivered 8.0 μL/min at a constant applied voltage of 2 V for over 7 h of continuous operation. The best EOP produces a maximum stall pressure of 3.5 kPa at 3 V. These characteristics make it suitable for a variety of microfluidic/device applications.

Polyaniline-based composites serve as adsorbent materials for the removal of hazardous heavy metal impurities such as Cr(vi) from wastewater.

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In an attempt to replace gassing metal electrodes, a new type of redox-conducting polymer electrodes for non-gassing electroosmotic pumps is developed. The work describes the application of a redox-conducting poly(hydroquinone/benzoquinone) electrode which was synthesized by cationic polymerization of benzoquinone and containing protic ceramic frit membranes. Laboratory made electro-osmotic pump was tested with developed polymer electrodes by varying different membrane thickness, applied voltage and flow-opposing (stall) pressure. As expected, with decrease in membrane thickness, flow-rate was observed to increase and the maximum flux per unit applied voltage was ∼30.3 μL.min −1 .cm −2 .V −1 . The maximum stall pressure (at zero flow-rate) was ∼10.0 kPa at 3.0 V with a membrane of 1.5 mm thick; stall pressure increased with increase in applied voltage. The maximum value of thermodynamic efficiency obtained was 0.16%. The pump could be operated continuously at 1.5 V and 3.0 V with flow rates of 4.0 ± 1.0 and 14.0 ± 1.0 μL.min −1 , respectively. Obtained performance results vindicate the novel attempt of developing redox-conducting polymer for applications in microfluidic devices, such as insulin pumps used for diabetes management.

We investigated a base-promoted protocol for the intermolecular anti-Markovnikov hydroamidation of vinyl arenes with arylamides to furnish the arylethylbenzamides with excellent chemo- and regioselectivity. The reaction tolerates an extensive variety of functional groups and has been successfully extended with electronically varied handles, aminobenzamides, electron-rich/electron-deficient heterocyclic amides, and vinyl arenes to afford the hydroamidated products. Excellent chemoselectivity was observed for the amide group over amine. The proposed mechanism and vital role of the solvent was well supported by deuterium labeling studies and control experiments.

A series of novel furan-2-yl-1H-pyrazoles and their chemical precursors were synthesised and evaluated for their effectiveness at disrupting α-synuclein (α-syn) aggregation in vitro. The compounds were found to inhibit α-syn aggregation with efficacy comparable to the promising drug candidate anle138b. The results of this study indicate that compounds 8b, 8l and 9f may qualify as secondary leads for the structure-activity relationship studies aimed to identify the suitable compounds for improving the modulatory activity targeted at α-syn self-assembly related to Parkinson's disease.

We investigated the use of seaweed-derived agar-based composite films as sound absorbers. Nonporous and porous films of varying concentrations of agar (1% to 5% w/v) and their composite films with glycerol (5% w/w) as the plasticizer and nanocrystalline cellulose (2% to 10% w/w) as the reinforcement material were fabricated. Porous films, of about 80% porosity, were obtained by a freeze-drying technique and nonporous films by drying in a hot air oven. Scanning electron microscopy study showed that porous films had interconnected walls with a pore size of 10 μm. Measured acoustic absorption coefficients using the twomicrophone transfer function method revealed that the porous films were effective in sound absorption. The films of 5% w/v agar concentration had the highest sound absorption. The addition of glycerol enhanced sound absorption, due to the damping nature induced by it, whereas the addition of nanocrystalline cellulose to the glycerol-added films did not alter its acoustic properties.