To date, there are no antimicrobial agents available in the market that have absolute control over the growing threat of bacterial strains. The increase in the production capacity of antibiotics and the growing antibacterial resistance of bacteria have majorly affected a variety of businesses and public health. Bimetallic nanoparticles (NPs) with two separate metals have been found to have stronger antibacterial potential than their monometallic versions. This enhanced antibacterial efficiency of bimetallic nanoparticles is due to the synergistic effect of their participating monometallic counterparts. To distinguish between bacteria and mammals, the existence of diverse metal transport systems and metalloproteins is necessary for the use of bimetallic Au–Ag NPs, just like any other metal NPs. Due to their very low toxicity toward human cells, these bimetallic NPs, particularly gold–silver NPs, might prove to be an effective weapon in the arsenal to beat emerging drug-resistant bacteria. The cellular mechanism of bimetallic nanoparticles for antibacterial activity consists of cell membrane degradation, disturbance in homeostasis, oxidative stress, and the production of reactive oxygen species. The synthesis of bimetallic nanoparticles can be performed by a bottom-up and top-down strategy. The bottom-up technique generally includes sol-gel, chemical vapor deposition, green synthesis, and co-precipitation methods, whereas the top-down technique includes the laser ablation method. This review highlights the key prospects of the cellular mechanism, synthesis process, and antibacterial capabilities against a wide range of bacteria. Additionally, we also discussed the role of Au–Ag NPs in the treatment of multidrug-resistant bacterial infection and wound healing.

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Sensitivity with respect to physical change of any type of sensor depends upon structure of the sensor and sensing material. If sensor is sensitive with more than single physical change (pressure or temperature etc) than sensitivity will get affected because of conflict in impact due to multiple physical parameters. Depending upon the designer’s intuition and experience, a variety of shapes of sensor had been proposed which can bear both the pressure and temperature. To understand the influence of temperature and pressure on the linearity and sensitivity, pressure sensors has been designed having 50 μm thick square diaphragm is being simulated and analyzed. The effect of pressure on Temperature Coefficient of Resistivity (TCR) of poly-silicon pressure sensor has been investigated in this paper. The stresses tempted in the piezoresistors and dislocation created in diaphragm have been studied using finite element method (FEM). The physical characteristics of sensor have been determined within the temperature range from 10 °C to 100 °C under the pressure range of 0 to 100 psi. It has been observed that TCR reduces with increasing pressure up to 30 psi, and beyond this pressure, the TCR begins to increase and thus the TCR shows the duality in nature. At 100 psi pressure, the calculated TCR for the diaphragm is found of the order of ∼7.7 × 10−3 (/°C). Thus, in conclusion, the pressure range ∼40–100 psi is recommended as the optimal range to achieve the better sensitivity. The temperature sensitivity of designed sensor has been found to be ∼0.10455 mV °C−1 while the pressure sensitivity of the proposed sensors which has been found to be 1.20051 mV psi−1. Hence, designed sensor can be used as both pressure and temperature sensing device incorporated into a single sensor.

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This paper reports the stress and frequency analysis of dynamic silicon diaphragm during the simulation of micro-electro-mechanical-systems (MEMS) based piezoresistive pressure sensor with the help of finite element method (FEM) within the frame work of COMSOL software. Vibrational modes of rectangular diaphragm of piezoresistive pressure sensor have been determined at different frequencies for different pressure ranges. Optimal frequency range for particular applications for any diaphragm is a very important so that MEMS sensors performance should not degrade during the dynamic environment. Therefore, for the MEMS pressure sensor having applications in dynamic environment, the diaphragm frequency of 280 KHz has been optimized for the diaphragm thickness of 50 [Formula: see text]m and hence this frequency can be considered for showing the better piezoresistive effect and high sensitivity. Moreover, the designed pressure sensor shows the high linearity and enhanced sensitivity of the order of ([Formula: see text]0.5066 mV/psi).