Conformational analysis of nucleic acids. Determination of backbone geometry of single-helical RNA and DNA in aqueous solution

2010 ◽  
Vol 101 (12) ◽  
pp. 413-433 ◽  
Author(s):  
C. Altona
1987 ◽  
Vol 20 (1-2) ◽  
pp. 35-112 ◽  
Author(s):  
Dinshaw J. Patel ◽  
Lawrence Shapiro ◽  
Dennis Hare

The early NMR research on nucleic acids was of a qualitative nature and was restricted to partial characterization of short oligonucleotides in aqueous solution. Major advances in magnet design, spectrometer electronics, pulse techniques, data analysis and computational capabilities coupled with the availability of pure and abundant supply of long oligonucleotides have extended these studies towards the determination of the 3-D structure of nucleic acids in solution.


1969 ◽  
Vol 23 (3) ◽  
pp. 671-682 ◽  
Author(s):  
A. B. Mcallan ◽  
R. H. Smith

1. Procedures, based on those of Schmidt & Thannhauser (1945) and Schneider (1945), for the extraction and estimation of nucleic acids in bovine digesta were examined in detail.2. Final methods which were suitable for routine determination of RNA and DNA were essentially as follows. Digesta samples were extracted in the cold, first with a solution of trichloroacetic acid in ethanol, then with aqueous trichloroacetic acid solution and finally with lipid solvents. The dried residue was hydrolysed with alkali, purified by passage through a Dowex resin, and the RNA, in the form of mononucleotides, determined by U.V. absorption. DNA was determined separately in hot perchloric acid extracts of the original dried residue by colorimetric estimation of the deoxyribose content.


1964 ◽  
Vol 42 (11) ◽  
pp. 1471-1480 ◽  
Author(s):  
E. Gordon Young

The method of Smillie and Krotkov has been applied to the estimation of soluble ribonucleic acid and deoxyribonucleic acid in nine species of marine algae, representative of the Chlorophyceae, Rhodophyceae, and Phaeophyceae. Treatment of the extract with an anion exchange resin was essential for the determination of RNA. Values for RNA and DNA, expressed as percentages of total solids, were respectively as follows: Ulva lactuca 0.63 and 0.10, Chondrus crispus 0.91 and 0.65, Rhodymenia palmata 0.73 and 0.41, Porphyra umbilicalis 1.62 and 0.19, Furcellaria fastigiata 0.37 and 0.36, Laminaria longicruris 0.68 and 0.06, L. digitata 0.67 and 0.30, L. agardhii 0.90 and 0.07, Fucus vesiculosus 0.29 and 0.05, based on commercial nucleic acids assayed by ultraviolet absorption, as standards. Use of ribose and deoxyribose as standards gave lower results. Attempts to prepare pure polynucleotides from several marine algae were unsuccessful.


2020 ◽  
Vol 16 (5) ◽  
pp. 748-756
Author(s):  
Mir Waqas Alam ◽  
Tentu Nageswara Rao ◽  
Yarasani Prashanthi ◽  
Vourse Sridhar ◽  
Adil Alshoaibi ◽  
...  

Background: Herbicides are very beneficial in the crop yield with the aid of controlling weeds within the agriculture, but several herbicides are chronic in soil. Objective: In this study, nanoparticles and the packages of synthesized novel silica nanoparticles were studied for the preconcentration of herbicides. Methods: These nanoparticles prepared by the Stöber mechanism were purified and functionalized. Nanoparticles thus prepared successfully were used as supporting material for the preconcentration of residues of herbicides in the water. Results: Preconcentration was achieved by preparing the silica-based solid-phase-extraction cartridges. Nanoparticles used for this purpose were within the range of 50-250 nm. An SPE cartridge was prepared by packing 200 mg of silica nanoparticle in the empty cartridge of diameter 5.5 cm and length 0.6 cm in between PTFE frits. Aqueous solutions of 0.1 μg/ml of herbicides were prepared separately, and 10 ml of the solution was passed through the cartridge at the rate of 0.2 ml/min. After passing 10 ml volume of the aqueous solution, residues adsorbed on the cartridge were eluted using 2 ml of acetonitrile. The eluate was injected to determine the herbicide residue adsorbed on the SPE cartridge. Conclusion: In the study, it was found that greater than 90% of the herbicide residues were trapped on silica nanoparticle-based SPE cartridge. An analytical method was developed for the simultaneous determination of these herbicides. The residues were quantified by LC-MS/MS with ESI mode.


1983 ◽  
Vol 29 (8) ◽  
pp. 1513-1517 ◽  
Author(s):  
M W McGowan ◽  
J D Artiss ◽  
B Zak

Abstract A procedure for the enzymatic determination of lecithin and sphingomyelin in aqueous solution is described. The phospholipids are first dissolved in chloroform:methanol (2:1 by vol), the solvent is evaporated, and the residue is redissolved in an aqueous zwitterionic detergent solution. The enzymatic reaction sequences of both assays involve hydrolysis of the phospholipids to produce choline, which is then oxidized to betaine, thus generating hydrogen peroxide. The hydrogen peroxide is subsequently utilized in the enzymatic coupling of 4-aminoantipyrine and sodium 2-hydroxy-3,5-dichlorobenzenesulfonate, an intensely red color being formed. The presence of a non-reacting phospholipid enhances the hydrolysis of the reacting phospholipid. Thus we added lecithin to the sphingomyelin standards and sphingomyelin to the lecithin standards. This precise procedure may be applicable to determination of lecithin and sphingomyelin in amniotic fluid.


1979 ◽  
Vol 6 (1-4) ◽  
pp. 409-412 ◽  
Author(s):  
Y. C. Jean ◽  
J. H. Brewer ◽  
D. G. Fleming ◽  
D. M. Garner ◽  
D. C. Walker

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