China
Africa
Explore chapters and articles related to this topic
Biomedical Applications IV: Carbon Nanotube-Nucleic Acid Complexes for Biosensors, Gene Delivery and Selective Cancer Therapy
Published in Giorgia Pastorin, carbon nanotubes, 2019
Makam Venkata Sudheer, Cang-Rong Jason Teng, Yoong Sia Lee, Pastorin Giorgia
DNA molecule contains three constituents, namely phosphate acid groups, basic groups and sugar units. The basic groups are adenine, guanine, cytosine and thymine, while in RNA thymine is replaced by the uracil residue. The structure of the DNA consists of two molecular chains, in which one chain is tightly bound to the other to form a double helix and they are held together by many hydrogen bonds. Further, DNA is classified as a natural polymer, and it has shown interesting solubilising properties of numerous materials as well as high sensitivity towards complementary sequences. On the other hand, a wide variety of applications of matrices made of CNTs for the detection of bio-organic and inorganic compounds has also been reported.8-11
Fundamental Aspects
Published in Bruno Langlais, David A. Reckhow, Deborah R. Brink, Ozone in Water Treatment, 2019
Guy Bablon, William D. Bellamy, Marie-Marguerite Bourbigot, F. Bernard Daniel, Marcel Doré, Françoise Erb, Gilbert Gordon, Bruno Langlais, Alain Laplanche, Bernard Legube, Guy Martin, Willy J. Masschelein, Gilbert Pacey, David A. Reckhow, Ciaire Ventresque
Another very important class of chemical components in cell constituents is the nucleobases derived from purine (adenine and guanine) and pyrimidine (uracil, thymine, and cytosine). One of these bases, a ribose (or deoxyribose) and phosphoric acid linked together by carbon-nitrogen and carbon-oxygen bonds, constitutes a class of nucleotide precursors of the nucleic acids, ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Lastly, adenine is a part of the structure of other molecules of interest, such as adenosine triphosphate or other substituted nucleotides, including three essential coenzymes (NAD+, FAD, and Co A).
Pyrimidines
Published in Mihai V. Putz, New Frontiers in Nanochemistry, 2020
Nicoleta A. Dudaş, Mihai V. Putz
Besides pyrimidine and purine nitrogenous bases from DNA and RNA (cytosine, thymine, uracil, adenine, guanine) there are many compounds containing the pyrimidine core which can be found in important classes such as vitamins or α-amino acids. Among them there are: thiamine (vitamin B1), riboflavin (vitamin B2), folic acid (vitamin B9), orotic acid (vitamin B13) and the nonproteogenic α-amino acid willardiine extracted from the seeds of various species of Acacia sp. and lathyrine (tingitanine) extracted from Lathyrus tingitanus (Figure 41.1) (Dudaş & Putz, 2014; McDowell, 2000; Lanska, 2009; Hoffbrand & Weir, 2001; Lagoja, 2005; Gmelin, 1959; Bell, 1961; Bell & Foster, 1962).
Enhanced coagulation process for removing dissolved organic matter, microplastics, and silver nanoparticles
Published in Journal of Environmental Science and Health, Part A, 2022
Suthiwan Keawchouy, Warangkana Na-Phatthalung, Dararat Keaonaborn, Juthamas Jaichuedee, Charongpun Musikavong, Suthatip Sinyoung
This work used commercial powder of AgNPs in the coagulation process. We purchased the AgNPs (99.99% purity) from American Elements (the Materials Science Manufacturer, America). The commercial specifications of AgNPs are spherical with a size distribution of 80 − 100 nm and a surface area of 5.37 m2/g. The molecular weight is 107.87 g/mol. We prepared a stock solution of AgNPs according to the method described by Sousa and Teixeira.[58] The AgNP powder was suspended in deionized water and mixed homogeneously using a magnetic stirrer for 45 minutes and sonicated for 1 h using a Transonic ultrasonic bath (Elma, Switzerland).[31] In this work, the stock solution was freshly prepared daily and kept in a refrigerator at 4 °C to prevent any aging effects.
Synthesis, crystal structure determination, DFT calculation, and Hirshfeld surface analysis of a new Zn(II) complex with the guaninium ligand
Published in Journal of Coordination Chemistry, 2020
Klai Kacim, Christian Jelsch, Christine Lucas, Frédéric Lefebvre, Werner Kaminsky, Cherif Ben Nasr, Kamel Kaabi
Over the past decades, there has been a sizable research effort on rational design and elaboration of transition metal complexes due to their interesting structural, chemical, and physical properties such as storage of gas, separation of molecules, catalyzing the chemicals, and delivery of drugs [1–5]. The interaction between divalent metal cations and nucleic acids has also been widely studied due to their importance for DNA-replication, transcription, and metabolic processes [6–11]. It is well known that metal atoms that interact with nucleobases in DNA and RNA can modify hydrogen bonds and cause DNA oxidation, thereby affecting the formation of the double helix and causing mutation points [12, 13]. Metal ions can bind directly to nucleic acid bases via the oxygen or nitrogen atoms of the bases. Guanine is one of the purine bases that take place into the composition of nucleic acids (DNA or RNA) and carry their genetic information. In this context, the molecular architecture of transition-metal complexes containing nucleobases is very useful, giving various molecular geometric shapes and high-dimensional architectures [14]. The chemistry of zinc compounds is gaining great attention due to their interesting structural features, catechol oxidase, schizonticidal, antimalarial, antimicrobial, tumor photosensitizers, and their potential use as agricultural biocides [15–18]. When considering biologically relevant transition metals, zinc is the second most abundant element found within cells, behind iron. Zinc ions (Zn2+) are known to facilitate diverse protein functions that are essential for life [19].
Efficiency and Mechanism of Ciprofloxacin Hydrochloride Degradation in Wastewater by Fe3o4/Na2S2O8
Published in Ozone: Science & Engineering, 2018
Shengtao Jiang, Jianzhong Zhu, Zibo Wang, Min Ge, Huayue Zhu, Ru Jiang, Enmin Zong, Yujiang Guan
Ciprofloxacin hydrochloride (CIP) is one of the broad-spectrum quinolone antibacterial agents, with its antibacterial properties ranking the highest among currently applied quinolone antibiotics. But, with its high ecological toxicity and the difficulty in removing it by conventional water treatment technologies, it poses certain threats to the ecosystem (Ouyang et al. 2017; Maryam et al. 2017; Zhao et al., 2015). Owing to its low solubility, ciprofloxacin is usually made into ciprofloxacin hydrochloride. Ciprofloxacin hydrochloride is a white or light yellow crystalline powder, soluble in water, slightly soluble in methyl alcohol, very slightly soluble in ethanol, and hardly soluble in chloroform. Its solubility in water (25 °C) is 10 g/L (Mizukoshi et al. 2009). The molecular structure of ciprofloxacin hydrochloride is Figure 1.