Detection of Nicotine Effect on Colon Cells in a Plasmonic Platform

Introduction: Smoking as one of the causes of various diseases has encouraged worldwide studies on its adverse pharmacological effects on different organs. Nicotine may influence the smooth muscles of the colon and subsequently the gut motility, which leads to a change in the moving rate of digested material through the gastrointestinal tract.Methods: Among various techniques, optical detection methods benefit from non-contact and high-sensitivity for studying the early effect of nicotine on the cells. Thus, we used an optically ellipsometric method to get the fast and sensitive nicotine effect on the colon cell. Two-dimensional plasmonic platforms by gold deposition onto the polydimethylsiloxane polymer (PDMS) patterned substrate were used as the guest medium of the cell and the sample was excited by all of the visible region wavelengths at different exposure time and maintenance time.Results: Our results showed that the phase difference between each polarization increased by augmenting the exposure time of smoke over the cell at a fixed maintenance time and there was a general red-shift by increasing the maintenance time at a fixed exposure time.Conclusion: Using different exposure time to cigarette smoke, we optically showed that the cigarette containing the addicting chemical of nicotine had a direct effect on the cultured colon cells on our 2D biocompatible plasmonic chip. It demonstrated considerable changes in the amplitude and phase of the interacted light by injecting nicotine into the system with the aid of the label-free and non-invasive plasmonic technique

Evaluation of residence time on nitrogen oxides removal in non-thermal plasma reactor

Non-thermal plasma (NTP) has been introduced over the last few years as a promising after- treatment system for nitrogen oxides and particulate matter removal from diesel exhaust. NTP technology has not been commercialised as yet, due to its high rate of energy consumption. Therefore, it is important to seek out new methods to improve NTP performance. Residence time is a crucial parameter in engine exhaust emissions treatment. In this paper, different electrode shapes are analysed and the corresponding residence time and NOx removal efficiency are studied. An axisymmetric laminar model is used for obtaining residence time distribution numerically using FLUENT software. If the mean residence time in a NTP plasma reactor increases, there will be a corresponding increase in the reaction time and consequently the pollutant removal efficiency increases. Three different screw thread electrodes and a rod electrode are examined. The results show the advantage of screw thread electrodes in comparison with the rod electrode. Furthermore,between the screw thread electrodes, the electrode with the thread width of 1 mm has the highest NOx removal due to higher residence time and a greater number of micro-discharges. The results show that the residence time of the screw thread electrode with a thread width of 1 mm is 21% more than for the rod electrode

Grid dependency analysis of RTD.

<p>Grid dependency analysis of RTD.</p

An image of the produced plasma for the reactor with screw electrode with 1 mm gap between the threads.

<p>An image of the produced plasma for the reactor with screw electrode with 1 mm gap between the threads.</p

RTD at <i>x</i> = <i>10 cm</i> and <i>x</i> = <i>30 cm</i> inside the reactor for the screw thread electrode with 1 mm gap between the threads.

<p>RTD at <i>x</i> = <i>10 cm</i> and <i>x</i> = <i>30 cm</i> inside the reactor for the screw thread electrode with 1 mm gap between the threads.</p

The velocity vector field of flow inside the reactors with different threads.

<p>a) Screw thread electrode with 1 mm thread length, b) Screw thread electrode with 2 mm thread length, c) Screw thread electrode with 3 mm thread length, d) The rod electrode without any threads.</p

Image of the screw thread electrodes.

<p>Image of the screw thread electrodes.</p

Grid dependency analysis of velocity magnitude.

<p>a) x = 10 cm b) x = 30 cm.</p

Calculated residence time for various studied electrodes.

<p>Calculated residence time for various studied electrodes.</p

Effect of electrode configuration on NO_x removal efficiency.

<p><b>a</b>) at 9.9 kV_PP and different pulse frequencies b) at 19.2 kHz pulse frequency and different applied voltage.</p