Highly sensitive asymmetric and symmetric cancer sensors with ultra-high-quality factor and resolution power

Abstract In the paper, we proposed two new highly sensitive and compact biosensors with ultra-high-quality factors based on the 1-D binary photonic crystal (silicon/air thin layer) with a defect layer. The proposed asymmetric and symmetric biosensors have just a few periods (two to five) on both sides of the defect layer and the normal cell group (INOK) and cancer cells group (YD-10B) are considered for the studies. The effects of different parameters including silicon layer thickness, air layer thickness, defect layer thickness, substrate position, number of periods, and light incident angle are considered in the biosensor operation and the biosensors are optimized based on the sensitivity. The results demonstrate that the sensitivity and defect mode wavelength of the sensors are independent of the substrate position. However, the quality factor and FOM of the sensors significantly depend on the substrate position and they are improved significantly in the symmetric sensor (~ 37% improvement in optimum condition). Also, the high sensitivities of the sensors are maintained over a wide range of silicon and air thicknesses, which is a valuable achievement in the manufacturing process. Furthermore, the sensitivity of the optimized biosensors with a defect layer thickness of 10 microns and only two periods reaches S ~ 2811 nm/RIU which is an excellent sensitivity for an optical biosensor

Linear optimization with bipolar max-parametric hamacher fuzzy relation equation constraints

summary:In this paper, the linear programming problem subject to the Bipolar Fuzzy Relation Equation (BFRE) constraints with the max-parametric hamacher composition operators is studied. The structure of its feasible domain is investigated and its feasible solution set determined. Some necessary and sufficient conditions are presented for its solution existence. Then the problem is converted to an equivalent programming problem. Some rules are proposed to reduce the dimensions of problem. Under these rules, some of the optimal variables are found without solving the problem. An algorithm is then designed to find an upper bound for its optimal objective value. With regard to this algorithm, a modified branch and bound method is extended to solve the problem. We combine the rules, the algorithm, and the modified branch and bound method in terms of an algorithm to solve the original problem

Effect of laser intensity and exposure time on photothermal therapy with nanoparticles heated by a 793-nm diode laser and tissue optical clearing

Laser-induced thermotherapy is a promising method for cancer treatment, the outcome of which is affected by the exposure time. An inappropriate exposure time and laser intensity cause incomplete tumour destruction, tumour regrowth, and metastasis. Also possible is irreversible damage, i.e. death of healthy cells, and so numerical models are necessary to provide an optimised laser intensity and exposure time for different cancerous tumours. In this study, a model based on finite element method (FEM) is used for solving the bio-heat transfer equation and the Arrhenius equation describing tissue damage. The cancerous tumour is considered as a perfect cylinder with a diameter of 20 mm and a thickness of 2, 3, 4, and 5 mm, filled up by highly absorbing nanoparticles and surrounded by healthy cylindrical tissue with a diameter of 40 mm and a length of 10 mm, which ahs a low scattering coefficient due to optical clearing. The results show that 243 s is a safe and appropriate exposure time when a diode laser with a wavelength of 793 nm and intensity of 0.75 W cm−2 together with gold nanorods of concentration 0.0001 % is used for the treatment of a 3-mm-thick tumour. Then, the results are developed and extensive numerical simulations are used to reveal mathematical relationships between two critical parameters, input power and optimised exposure time, for a series of different tumour thicknesses. Treatment protocols are presented

The effect of precursor on the alumina ‎nanostructures synthesized by green method for ‎copper ions removal‏ ‏from industrial wastewater

Copper is one of the very harmful metals for human’s life, may lead to headaches, depression and learning disabilities, which is a very vital issue. Moreover, this metal is not biodegradable and remains in nature for a long time. Metal oxide nanoparticles with high surface adsorption can be used as a suitable option for copper removal from factory effluents. In this paper, aluminum oxide nanoparticles are proposed, synthesized and investigated as nanoparticles with high adsorption. Also, the synthesis is based on two different precursors (aluminum chloride and aluminum nitrate) and the effect of precursor is investigated on the structural and optical properties of alumina nanoparticles. Studies show that alumina nanoparticles are formed with both precursors, and they are amorphous. However, the choice of precursor has a significant effect on the size of the nanoparticles and the optical properties of these alumina nanoparticles. In addition, the study of the effect of precursor selection on the copper cation removal at pH = 5.7 shows that alumina nanoparticles synthesized with aluminum nitrate have better copper removal efficiency than the sample synthesized with aluminum chloride precursor and the removal of copper contaminants (20 ppm) with this alumina nanoparticles reaches 91% in 180 minutes, which indicates the excellent performance of synthesized nanoparticles in copper removal

The physical properties and photocatalytic activities of green synthesized ZnO nanostructures using different ginger extract concentrations

Abstract The green synthesis method which is aligned with the sustainable development goals (SDGs) theory, is proposed to synthesize ZnO nanoparticles using ginger extract to treat the acidic wastewater and acidic factory effluent as a current challenge and the effects of the concentration of extracts on the synthesized ZnO nanostructures are investigated. The results declare that the single-phase hexagonal ZnO is formed using ginger extract concentration of less than 25 mL and the crystallite size of green synthesized ZnO NPs increased with increasing the concentration of ginger extract. Also, the significant effects of ginger extract concentration on the morphology of nanoparticles (nanocone, nanoflakes, and flower-like) and the particle size are demonstrated. The low concentration of ginger extract leads to the formation of the ZnO nanoflakes, while the flower-like structure is gradually completed by increasing the concentration of the ginger extract. Furthermore, significant changes in the specific surface area (SSA) of the samples are observed (in the range of 6.1–27.7 m2/g) by the variation of ginger extract concentration and the best SSA is related to using 10 mL ginger extract. Also, the strong effect of using ginger extract on the reflectance spectra of the green synthesized ZnO NPs, especially in the UV region is proved. The indirect (direct) band gap energies of the ZnO samples are obtained in the range of 3.09–3.20 eV (3.32–3.38 eV). Furthermore, the photocatalytic activities of the samples for the degradation of methylene blue indicate the impressive effect of ginger extract concentration on the degradation efficiency of ZnO nanoparticles and it reaches up to 44% and 83% for ZnO NPs prepared using 5 mL ginger extract in a pH of 4.3 and 5.6, respectively. This study provided new insights into the fabrication and practical application of high-performance ZnO photocatalysts synthesized using ginger extract in degrading organic pollutants in an acidic solution

Laser‐induced optothermal response of gold nanoparticles: From a physical viewpoint to cancer treatment application

Gold nanoparticles (GNPs)-based photothermal therapy (PTT) is a promising minimally invasive thermal therapy for the treatment of focal malignancies. Although GNPs-based PTT has been known for over two decades and GNPs possess unique properties as therapeutic agents, the delivery of a safe and effective therapy is still an open question. This review aims at providing relevant and recent information on the usage of GNPs in combination with the laser to treat cancers, pointing out the practical aspects that bear on the therapy outcome. Emphasis is given to the assessment of the GNPs' properties and the physical mechanisms underlying the laser-induced heat generation in GNPs-loaded tissues. The main techniques available for temperature measurement and the current theoretical simulation approaches predicting the therapeutic outcome are reviewed. Topical challenges in delivering safe thermal dosage are also presented with the aim to discuss the state-of-the-art and the future perspective in the field of GNPs-mediated PTT. This article is protected by copyright. All rights reserved