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In this paper, half-cylindrical-shaped rods are arranged in a row in order to form hemoglobin concentration sensors. The proposed structures can effectively detect hemoglobin concentrations in blood samples. Five individual structures based on graphene-plasmonic combinations are proposed and investigated. The proposed structures are made of different layers of Au, Ag, SiO 2 , and graphene. Different plates and cylindrical-shaped graphene layers are introduced in the structures to improve the functionality (absorption peak value and wavelength) of the absorber (sensor). Adding more Au layers strengthens the confinement of the incident electromagnetic waves and improves the absorption factor. Also, in the proposed structures, for improving the results, the effects of the chemical potential of graphene layers and "G" (graphene layer thicknesses) on the absorption peak and wavelength are considered. The final suggested structure indicates unity absorption peak and thus can be utilized in wide ranges of applications. As a refractive index bio-sensor, the structure is considered for detecting hemoglobin concentrations in blood samples which indicates a reasonable sensitivity factor of 570 nm/RIU., Competing Interests: Conflict of InterestThe authors declare no competing interests., (© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2021.)

Intra-abdominal adhesions following surgery are a challenging problem in surgical practice. This study fabricated different thermoplastic polyurethane (TPU) nanofibers with different average diameters using the electrospinning method. The conditions were evaluated by scanning electron microscopy (SEM), atomic force microscope (AFM), and Fourier transform infrared spectrometer (FTIR) analysis. A static tensile test was applied using a strength testing device to assess the mechanical properties of the electrospun scaffolds. By changing the effective electrospinning parameters, the best quality of nanofibers could be achieved with the lowest bead numbers. The electrospun nanofibers were evaluated in vivo using a rat cecal abrasion model. The macroscopic evaluation and the microscopic study, including the degree of adhesion and inflammation, were investigated after three and five weeks. The resultant electrospun TPU nanofibers had diameters ranging from about 200 to 1000 nm. The diameters and morphology of the nanofibers were significantly affected by the concentration of polymer. Uniform TPU nanofibers without beads could be prepared by electrospinning through reasonable control of the process concentration. These nanofibers' biodegradability and antibacterial properties were investigated by weight loss measurement and microdilution methods, respectively. The purpose of this study was to provide electrospun nanofibers having biodegradability and antibacterial properties that prevent any adhesions or inflammation after pelvic and abdominal surgeries. The in vivo experiments revealed that electrospun TPU nanofibers reduced the degree of abdominal adhesions. The histopathological study confirmed only a small extent of inflammatory cell infiltration in the 8% and 10% TPU. Conclusively, nanofibers containing 8% TPU significantly decreased the incidence and severity of postsurgical adhesions, and it is expected to be used in clinical applications in the future., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Ahmad Gholami et al.)

A new technique for cancer therapy is Photo Thermal Therapy (PTT). In the PTT technique, photon energy is converted into heat via various operations to destroy malignant tumors. Carbon nanotubes (CNTs) have good optical absorption in the near-infrared (NIR) spectrum and could transform optical energy into heat to induce hyperthermia in the PTT method. In this study, CNTs were firstly oxidized (O-CNT) and then decorated with silver nanoparticles (Ag NPs). Polyethylene glycol (PEG) was utilized for wrapping the surface of CNTs (O-CNT/Ag-PEG). Coating of CNTs with Ag NPs and PEG was confirmed by XRD, FESEM, and TEM techniques. Results demonstrated that noble metal could increase optical absorption of CNTs and concurrently improve the efficacy of the PTT technique. Cell cytotoxicity study showed that O-CNT/Ag NPs were less cytotoxic than O-CNTs, and O-CNT/Ag-PEG had the lowest toxicity against HeLa, HepG2, and PC3 human cell lines. The efficacy of O-CNT/Ag-PEG NPs in destroying malignant melanoma tumors was evaluated through the PTT technique. A continuous wave NIR laser diode (λ = 808 nm, P = 2 W, and I = 2 W/cm 2 ) irradiated the tumor sites for 8 min once in the period of the treatment. The tumors in cases receiving O-CNT/Ag-PEG were shrunk efficiently compared to laser treatment ones. Results of in-vivo studies demonstrated that O-CNT/Ag-PEG was a puissant candidate in extirpating malignant tumors in PTT method.

Objective: In the current study we have stimulated the efficacy of plasmonic nanoparticles (NPs) by laser hyperthermia to achieve a less invasive method for tumor photothermal therapy of benign prostatic hyperplasia (BPH)., Methods: The levels of apoptosis on induced BPH in rats were assessed after treatment and revealed and recorded by various assayed. Moreover, the expression of caspases was considered to demonstrate the apoptotic pathways due to laser induced plasmonic NPs., Results: In the Laser + NPs group prostate size of induced BPH decreased. Laser + NPs also decreased prostate specific antigen in comparison with the BPH groups. Furthermore, Laser + NPs attenuated BPH histopathologic indices in the rats. Laser + NPs induced apoptosis in prostatic epithelial cells via caspase-1 pathway., Conclusions: Altogether, the approach and findings from this study can be applied to introduce the laser irritated NPs method as a novel and less invasive therapy for patients suffering from BPH., Competing Interests: Declaration of Competing Interest There is no conflict of interest to declare., (Copyright © 2020 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

Objectives: Photo-thermal therapy (PTT) is a therapeutic method in which photon energy is converted into heat to induce hyperthermia in malignant tumor cells. In this method, energy conversion is performed by nanoparticles (NPs) to enhance induced heat efficacy. The low-cytotoxicity and high optical absorbance of NPs used in this technique are very important. In the present study, titanium dioxide (TiO 2 ) NPs were used as agents for PTT. For increasing water dispersibility and biocompatibility, polyethylene glycol (PEG)-TiO 2 NPs (PEGylated TiO 2 NPs) were synthesized and the effect of these NPs on reducing melanoma tumor size after PTT was experimentally assessed., Materials and Methods: To improve the dispersibility of TiO 2 NPs in water, PEG was used for wrapping the surface of TiO 2 NPs. The formation of a thin layer of PEG around the TiO 2 NPs was confirmed through thermo-gravimetric analysis and transmission electron microscopy techniques. Forty female cancerous mice were divided into four equal groups and received treatment with NPs and a laser diode (λ = 808 nm, P = 2 W & I = 2 W/cm 2 ) for seven min once in the period of the treatment., Results: Compared to the mice receiving only the laser therapy, the average tumor size in the mice receiving TiO 2 -PEG NPs with laser excitation treatment sharply decreased., Conclusion: The results of animal studies showed that PEGylated TiO 2 NPs were exceptionally potent in destroying solid tumors in the PTT technique., Competing Interests: The authors declare that they have no conflicts of interest. Authors disclose all relationships or interests that could have direct or potential influence or impart bias on the work.

Purpose: Plasmonic photo thermal therapy (PPTT) is a therapeutic method in which the photon energy is rapidly transformed into heat via a series of radiative and non-radiative phenomena to ablate cancer. Plasmonic NPs, such as silver NPs (Ag NPs), have considerable properties in optical absorbance. Furthermore, good thermal conductivity and cell penetration ability of carbon nanotubes (CNTs) could improve the efficacy of Ag NPs for PPTT. Decoration of the multi-walled carbon nanotubes (MWCNTs) with silver has been developed to enhance thermal conductivity of the MWCNT particles. Methods: The Ag NPs were decorated on the CNTs and the ability of these particles (CNT/Ag NPs) in reduction of melanoma tumor size after PTT was evaluated experimentally. For comparison, the PTT of silver nanorods (Ag NRs) and CNTs were investigated. The melanoma tumor was induced by injection of B16/F10 cell line to the inbred mice. Different NPs were injected into the tumors and then irradiated via laser diode (λ=670 nm, P=500 mW, and I= 3.5 W/cm 2 ) at scheduled time. Results: Monitoring of tumor sizes showed that integration of CNTs with silver could enhance the optical absorption of CNTs and improve tumor destruction in PPTT technique. Conclusion: The CNT/Ag NPs could act as a potent agent in PPTT method in curing solid tumors.

Photothermal therapy (PTT) is a therapeutic method in which photon energy is transformed into heat rapidly via different operations to extirpate cancer. Nanoparticles, such as carbon nanotubes (CNTs) have exceptional optical absorbance in visible and near infrared spectra. Therefore, they could be a good converter to induce hyperthermia in PTT technique. In our study, for improving the dispersibility of multiwalled CNTs in water, the CNTs were oxidized (O-CNTs) and then polyethylene glycol (PEG) was used for wrapping the surface of nanotubes. The formation of a thin layer of PEG around the nanotubes was confirmed through Fourier transform infrared, thermogravimetric analysis, and field emission scanning electron microscopy techniques. Results of thermogravimetric analysis showed that the amount of PEG component in the O-CNT-PEG was approximately 80% (w/w). Cell cytotoxicity study showed that O-CNT was less cytotoxic than pristine multiwalled nanotubes, and O-CNT-PEG had the lowest toxicity against HeLa and HepG2 cell lines. The effect of O-CNT-PEG in reduction of melanoma tumor size after PTT was evaluated. Cancerous mice were exposed to a continuous-wave near infrared laser diode (λ=808 nm, P =2 W and I =8 W/cm 2 ) for 10 minutes once in the period of the treatment. The average size of tumor in mice receiving O-CNT-PEG decreased sharply in comparison with those that received laser therapy alone. Results of animal studies indicate that O-CNT-PEG is a powerful candidate for eradicating solid tumors in PTT technique., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

A strip/slot hybrid arsenic tri-sulfide waveguide with a horizontal silicon dioxide slot is proposed. The waveguide exhibits an ultra-flat and low dispersion profile with four zero-dispersion wavelengths. Tuning structural parameters of the waveguide causes tailoring the dispersion. There is only a low dispersion of approximately ± 3 ps/(nm · km) over a 1035 nm bandwidth. It is shown that the waveguide has less sensitivity to the variations of the structural parameters and fabrication errors compared to silicon waveguides. Moreover, nonlinear coefficient, figure of merit, third-order dispersion and phase-matching condition in four-wave mixing are studied. This waveguide has a great potential for nonlinear applications in a wide range of wavelengths.

In this paper, two new organic light emitting diodes in near infrared (NIR) range were fabricated based on acceptor-donor-acceptor (A-D-A) and donor-acceptor-donor (D-A-D) oligomers. We found that, the electroluminescent (EL) spectra of these oligomers which have the wavelength range from 900 to 1150 nm. The maximum external quantum efficiencies (EQE) and electrical to optical power efficiencies for these devices were measured and they found to be (3.3%, 16.7 mW/W) and (1.32%, 6.6 mW/W) for A-D-A and D-A-D oligomers respectively.