Circular dichroism method

Yang, J.T., Wu, C.-S., and Martinez, H.M. 1986. Calculation of protein conformation from circular dichroism. Methods Enzymol. 1.30 208-269. 

A spectrophotometric method for the determination of ampicillin involving initial benzoylation of the side chain a-amino group is described. a-Benzamidobenzylpenicillin so formed is treated with mercuric chloride in acid solution and a-benzamidobenzylpenicillenic acid is obtained. This may be assayed spectrophoto-metricallyl69, Ampicillin is degraded in a buffer solution at pH 5.2 at 75°C and the absorbance is measured at 320 nm. Smith s method for the spectrophotometric determination of ampicillin was adapted to the assay of ampicillin in chicken blood, bile and urine 3-Ampicillin is dissolved in 5N sodium hydroxide and the absorbance is measured at 279 nm 2, Ampicillin is determined spectrophotometrically as its copper complex S. Spectrophotometric and circular dichroism methods for determining the activity of ampicillin are described. A... 

The complexings of D-glucose, D-fructose, and maltose with borate anions have been studied by polarimetric, conductivity, and pH measurements, and circular dichroism methods have been used to investigate the complexing of cuprammonium ions with carbohydrate diols and amino-alcohols. An examination of the c.d. spectra of fifteen methyl 3-acetamido-3,6-dideoxyhexopyranoside derivatives measured in methanol, 2,2,2-trifluoroethanol, and acetonitrile su ests that the amide group is not completely planar and may show chirality. The n it transition of the carboxylic acid carbonyl groups at... 

R81 S.-D. Zhao, L. Shen, D.-Q. Luo and H.-J. Zhu, Progression of Absolute Configuration Determination in Natural Product Chemistry Using Optical Rotation (Dispersion), Matrix Determinant, and Electronic Circular Dichroism Methods , Curr. Org. Chem., 2011, 15, 1843. 

The studies by means of NMR and circular dichroism methods [29] made it possible to identify the presence of relatively rigid and more flexible structures alternating within a single hyaluronan chain with a balance between these structures. Extremely high viscosity of hyaluronan solutions was due, on the one hand to its structure and, on the other hand, was conditioned by specific and non-specific intermolecular interactions of macromolecules [29]. It all points to the fact that not only hydrophilic but also hydrophobic interactions play a significant role in stabilization of hyaluronan structure associated with the specific macromolecular structure. 

Botha J J, Ferreira D, Roux D G 1978 Condensed tannins Circular dichroism method of assessing the absolute configuration at C-4 of 4-arylflavan-3-ols and stereochemistry of their formation from flavan-3,4-diols. J Chem Soc Chem Commun 698-700... 

Thomson, A.J., Cheesman, M.R., George, S.J. Variable-temperature magnetic circular dichroism. Methods Enzymol. 226, 199-232 (1993)... 

Sivaraman, B., Fears, K.P., Latour, R.A. Investigation of the effects of surface chemistry and solution concentration on the conformation of adsorbed proteins using an improved circular dichroism method. Langmuir 25(5), 3050-3056 (2009)... 

Chiroptical techniques allow optical distinction between chiral molecules. In the ORD (optical rotatory dispersion) method the optical rotation is recorded as a function of the wavelength. In the CD (circular dichroism) method the difference in molar absorptivity between left and right circularly polarized light is measured as a function of the wavelength. The ORD curve of (-) humulone in methanol is displayed in Fig. 4. 

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