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Application of Next-Generation Plant-Derived Nanobiofabricated Drugs for the Management of Tuberculosis
Published in Richard L. K. Glover, Daniel Nyanganyura, Rofhiwa Bridget Mulaudzi, Maluta Steven Mufamadi, Green Synthesis in Nanomedicine and Human Health, 2021
Charles Oluwaseun Adetunji, Olugbenga Samuel Michael, Muhammad Akram, Kadiri Oseni, Ajayi Kolawole Temidayo, Osikemekha Anthony Anani, Akinola Samson Olayinka, Olerimi Samson E, Wilson Nwankwo, Iram Ghaffar, Juliana Bunmi Adetunji
In UV-vis absorption spectroscopy, optical properties are determined by the use of absorbance spectroscopy. This absorbance is measured to determine the concentration of this solution using Beer–Lambert theory. Iron nanoparticles synthesized using suitable surface plasmon resonance with high-band intensities and peaks from Azadirachta indica was determined through the use of UV-vis spectroscopy at the range of 216–265 nm (Monalisa and Nayak, 2013).
Light, Matter, and Spectroscopy
Published in Patrick E. McMahon, Rosemary F. McMahon, Bohdan B. Khomtchouk, Survival Guide to General Chemistry, 2019
Patrick E. McMahon, Rosemary F. McMahon, Bohdan B. Khomtchouk
An electron can absorb one photon to move from an initial lower electron energy level to a final higher energy level. Absorption spectroscopy measures the wavelengths of light that are absorbed during electron transitions in an atom. The selected wavelengths (colors, if in the visible region of the spectrum) of absorbed photons appear as dark lines against a background of all other unabsorbed wavelengths of light.
Spectroscopic Techniques
Published in Ravindra Kumar Pandey, Shiv Shankar Shukla, Amber Vyas, Vishal Jain, Parag Jain, Shailendra Saraf, Fingerprinting Analysis and Quality Control Methods of Herbal Medicines, 2018
Ravindra Kumar Pandey, Shiv Shankar Shukla, Amber Vyas, Vishal Jain, Parag Jain, Shailendra Saraf
UV absorption spectroscopy is one of the best methods for determination of impurities in organic molecules. Additional peaks can be observed due to impurities in the sample and can be compared with that of the standard raw material. By also measuring the absorbance at a specific wavelength, the impurities can be detected. UV spectroscopy is useful in the structure elucidation of organic molecules, the presence or absence of unsaturation, and the presence of hetero atoms (Gupta et al., 2005). From the location of peaks and combinations of peaks, it can be concluded whether the compound is saturated or unsaturated, hetero atoms are present or not, and so on. UV absorption spectroscopy can characterize those types of compounds which absorbs UV radiation. Identification is done by comparing the absorption spectrum with the spectra of known compounds. Many herbal drugs are either in the form of raw material or in the form of formulations. They can be assayed by making a suitable solution of the drug in a solvent and measuring the absorbance at a specific wavelength (Agarwal and Paridhavi, 2012). Molecular weights of herbal compounds can be measured spectrophotometrically by preparing the suitable derivatives of these compounds.
Facile biosynthesis, characterisation and biotechnological application of ZnO nanoparticles mediated by leaves of Cnidoscolus aconitifolius
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2023
Reuben Samson Dangana, Reama Chinedu George, Umulkhayr Oyenike Shittu, Femi Kayode Agboola
The absorption spectrum showed a characteristic peak at 350 nm of the green synthesised ZnO NPs (Figure 1). The energy gap was calculated as 3.3 eV which is consistent with previous research [65]. UV-VIS absorption spectroscopy is a widely used technique to examine the optical properties of nanosized particles [66]. Surface Plasmon Resonance (SPR) is responsible for the unique optical properties of ZnO NPs by factors such as particle size, particle shape, their distance from each other (concentration) and refractive index of the changes in the surrounding environment [43]. The surface plasmon resonance (SPR) of ZnO NPS is between 310–380 nm [44]. The UV-Vis spectra, revealed that the plant extract contains phytochemicals that are UV-Vis active with peaks around 275–278 nm and another around 316 nm. On the formation of ZnO NP (red line), the peak at 316 disappears and there is a gentle sloping peak of 371 nm, while the PE peak at shifted to lower wavelength (269 nm).
Nanoparticle-protein corona complex: understanding multiple interactions between environmental factors, corona formation, and biological activity
Published in Nanotoxicology, 2021
Aysel Tomak, Selin Cesmeli, Bercem D. Hanoglu, David Winkler, Ceyda Oksel Karakus
UV-vis absorption spectroscopy can also be used to study protein structure and function. The binding of proteins to NPs leads to changes in UV-vis absorption spectra that can be used to measure binding affinities for different combinations of proteins and NPs (Mahmoudi et al. 2011). Casals et al. (2010) measured the UV-vis spectra of AuNPs before and after exposure to protein-containing medium and observed a redshift (shift to longer wavelengths) of the plasmonic resonance absorption peak due to conjugation of proteins to NPs. While UV-vis spectroscopy is a practical method for the fast and simple qualitative description of NP-protein interactions, it is highly susceptible to environmental conditions (e.g. temperature, pH, electrolyte, and presence of interfering substances) and is, therefore, not sufficient on its own to characterize binding affinities of proteins to NPs.
New Multi-Walled carbon nanotube of industrial interest induce cell death in murine fibroblast cells
Published in Toxicology Mechanisms and Methods, 2021
Krissia Franco de Godoy, Joice Margareth de Almeida Rodolpho, Patricia Brassolatti, Bruna Dias de Lima Fragelli, Cynthia Aparecida de Castro, Marcelo Assis, Juliana Cancino Bernardi, Ricardo de Oliveira Correia, Yulli Roxenne Albuquerque, Carlos Speglich, Elson Longo, Fernanda de Freitas Anibal
The absorption and fluorescence spectroscopy of OCNT-TEPA is shown in Figure 3. In absorption spectroscopy, the spectrometer casts a beam of light into the cuvette, collects the remaining light on the other side, so that we can see which wavelengths were absorbed or not at a given wavelength. This analysis then becomes important considering the objective of checking the fluorescence of OCNT-TEPA, since to understand the fluorescence spectrum it is also necessary to understand the absorption spectrum. In the absorption spectra we observed that the cuvette and the water remain as a baseline, but analyzing the OCNT-TEPA, we observed the scattering of the absorption light, with no peak or absorption bands in this range (400–800 nm) which is in agreement with this class of nanomaterial (Figure 3(a)) (Shetty et al. 2009; Yang et al. 2016). Analyzing the various concentrations of the OCNT-TEPA nanoparticle, we observed that the fluorescence curve pattern did not change compared with water. At higher concentrations the spectrum decreases their signal due to greater scattering of light that OCNT-TEPA can induce, decreasing the fluorescence emission signal (Figure 3(b)).