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Non-Photocatalytic and Photocatalytic Inactivation of Viruses Using Antiviral Assays and Antiviral Nanomaterials
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Suman Tahir, Noor Tahir, Tajamal Hussain, Zubera Naseem, Muhammad Zahid, Ghulam Mustafa
QDs are the semiconductor material with a typical dimension of 2–10 nm and are extensively utilised for image tracking, virus and cell labelling, and detection because of their renowned luminescent characteristics; these characteristics include narrow and bright emission spectroscopy, broad excitation spectroscopy, size-dependent emission wavelengths, and long fluorescence lifetime (Chen et al. 2018). However, limited reports are available on the utilisation of QDs as an antiviral candidate. The glutathione (GSH)-based cadmium telluride (CdTe) QDs were investigated; it was established that they varied PRV surface proteins structure, preventing the viral entrance into host cells (Du et al. 2015). Moreover, attaching of CdTe QDs to cell membrane itself lessened the virus count. The antiviral impact of carbon dots (CDots) with less toxic action were investigated with PRRSV and PRV as trial models of RNA and DNA viruses. The CDots meaningfully suppressed replication of both PRRSV and PRV.
Modeling the Imaging Performance of Photon Counting X-Ray Detectors
Published in Katsuyuki Taguchi, Ira Blevis, Krzysztof Iniewski, Spectral, Photon Counting Computed Tomography, 2020
Early efforts to model the performance of photon-counting x-ray detectors include those of Michel and colleagues,(28,29) who developed a model of the zero-frequency DQE under the assumption of low count rates such that pulse pile-up effects are negligible. Michel and colleagues related mathematically the zero-frequency DQE to the first and second statistical moments of what they termed the multiplicity, which is the number of detected photons relative to the number of interacting photons. In photon-counting systems, it is possible to record multiple photons per interaction when photon energy is spread over multiple elements. Michel and colleagues showed that the zero-frequency DQE is proportional to the square of the average multiplicity divided by the second moment of the distribution of multiplicities. They showed that the zero-frequency DQE degrades as the multiplicity increases, which was a novel result. Koenig and colleagues used the multiplicity concept to investigate the DQE of cadmium telluride (CdTe) detectors.(30) More recently, Ji and colleagues modeled theoretically the first and second moments of the multiplicity and calculated the zero-frequency DQE of CdTe detectors.(31)
Molecular Targets and Optical Probes
Published in George C. Kagadis, Nancy L. Ford, Dimitrios N. Karnabatidis, George K. Loudos, Handbook of Small Animal Imaging, 2018
Eleni K. Efthimiadou, George Kordas
The synthesis of QDs was described in 1982 by Efros and Ekimov (Efros and Efros 1982; Ekimov and Onushchenko 1982). Nanocrystals and microcrystals of semiconductors were introduced into glass matrices and their optical properties were studied. Based on this work, a wide variety of synthetic methods have been developed for the synthesis of QDs in different solutions, including aqueous, high-temperature organic solvents, and solid materials (Bailey and Nie 2003; Zhong et al. 2003). It is well known that the synthesized QDs, after introducing semiconductor precursors, form crystals under thermodynamically favorable conditions. Semiconductor-binding agents kinetically control crystal growth, aiming at maintaining their size within the quantum size. A significant input to QDs’ synthesis was introduced in 1993 by Murray et al. (1993), developing monodispersed QDs made from cadmium sulfide (CdS), cadmium selenide (CdSe), or cadmium telluride (CdTe). Based on this report, the synthetic chemistry of CdSe QDs generated brightly fluorescent QDs that could span the visible spectrum. As a result, CdSe has become the most common chemical composition for QD synthesis, especially for biological applications.
Three-dimensional (3D) cell culture studies: a review of the field of toxicology
Published in Drug and Chemical Toxicology, 2023
Seda İpek, Aylin Üstündağ, Benay Can Eke
2D cultures, on the other hand, cannot always predict human reactions, despite being considered as an alternative form of animal testing (Leite et al.2011). Also, although 2D cell cultures have greatly advanced our understanding of cell response and are widely accepted, growing evidence indicates that 2D cell culture models can lead to cell bioactivities that are significantly different from what occurs in vivo (Duval et al.2017). Furthermore, 2D culture substrates not only are incapable of reproducing the dynamic, complex environments of in vivo tissues, but also have the potential to generate misrepresent the results since they force cells to adapt to an artificial, flat and rigid surface (Table 1) (Mazzoleni et al.2009). Zhang et al. (2019) generated a 3D A549 lung carcinoma cell model to investigate the cellular effects of cold atmospheric plasma (CAP). They also compared the results from the 3D model with those from the 2D A549 cell line. CAP exhibited lower cytotoxicity in the 3D model than in 2D cells. Lee et al. (2009) generated a 3D spheroid culture system using hydrogel inverted colloidal crystal (ICC) scaffolds to form a physiologically pertinent model of liver tissue. The 3D culture system provided a more tissue-like morphology and phenotypes properties and resulted in decreased cytotoxic effects of the cadmium telluride and gold nanoparticles in the 3D spheroid model.
Emerging theranostics to combat cancer: a perspective on metal-based nanomaterials
Published in Drug Development and Industrial Pharmacy, 2022
Tejas Girish Agnihotri, Shyam Sudhakar Gomte, Aakanchha Jain
These are special kinds of chemicals that have characteristics of both metals and nonmetals and are difficult to categorize into metals and nonmetals. They are also called semi-metals and have different biological effects on tissues or cells. For example, arsenic exists as a metalloid or semi-metal in two biologically significant oxidation forms, As (V) and As (III), and its position as a carcinogen and/or medicinal agent has remained a contentious topic. These NPs are also employed for diagnostic purposes. For in vivo imaging and CT, cadmium telluride NPs and polymer-coated bismuth sulfide NPs were used as quantum dots [94]. Liubov et al. [95] fabricated silicon-based metalloid NPs for cancer theranostic applications. The silicon NPs were prepared by mechanical mixing of pure silicon and employed in the detection of living cells. It was observed from the studies that NPs assisted in penetrating the tumor cells, without producing any cytotoxic effects on normal cells up to a concentration of 100 µg/mL and act as photosensitizers that can be employed in the photodynamic therapy of cancer.
PEG-PLGA- hybrid nanoparticles loaded with etoricoxib – phospholipid complex for effective treatment of inflammation in rat model
Published in Journal of Microencapsulation, 2019
Vivek Dave, Prarthana Srivastava, Kajal Tak, Swapnil Sharma
The quantitative analysis of the sample for the presence of different functional groups in the structure was characterised by Bruker EQUINOX 55 FTIR. Using ATR-FTIR instrument drug (Etoricoxib), polymer (poly lactic co glycolic acid), Lipid (Phospholipon 90 G), TGPS, MPEG-DSPE2000 and optimised formulations were scanned. All the samples were scanned at room temperature. Instrument was furnished with mercury cadmium telluride (MCT) detector with nominal resolution of 2 cm−1. For internal reflection diamond was used placed at an incidence angle of 45°. Innovative ATR rectification was applied for all spectra, peaks were analysed from 4000 to 400 cm−1 and peak fitting was done through opus software.