Reversible and irreversible denaturation processes in globular proteins: from collective to molecular spectroscopic analysis

Drug-protein interaction is a fundamental problem in estimating the serious side effects of the drug. Hence, the main objective of this study was to study the interaction of acarbose with three different globular proteins i.e.; bovine serum albumin (BSA), human serum albumin (HSA), and hemoglobin (Hb) via UV-Visible absorption spectroscopic analysis. We were determined physicochemical parameters, binding constant, distribution constant and thermodynamic parameters activation energy, enthalpy, entropy, and Gibbs free energy by using UV-visible data. These both properties of acarbose-protein complexes indicated that the hydrogen bonding and weak van der Waals force played a major role in the interaction for complexation. The binding of acarbose with different proteins leads to change in the structure of protein folding which confirms by physicochemical and thermodynamic analysis.

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Albumins as Embedding Media for Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064025 ◽

1969 ◽

Vol 27 ◽

pp. 422-423 ◽

Cited By ~ 1

Author(s):

J. L. Farrant ◽

J. D. McLean

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

High Temperature ◽

Biological Material ◽

Globular Proteins ◽

The Past ◽

Antibody Staining ◽

Thin Sectioning ◽

Embedding Medium

For electron microscope techniques such as ferritin-labeled antibody staining it would be advantageous to have available a simple means of thin sectioning biological material without subjecting it to lipid solvents, impregnation with plastic monomers and their subsequent polymerization. With this aim in view we have re-examined the use of protein as an embedding medium. Gelatin which has been used in the past is not very satisfactory both because of its fibrous nature and the high temperature necessary to keep its solutions fluid. We have found that globular proteins such as the serum and egg albumins can be cross-linked so as to yield blocks which are suitable for ultrathin sectioning.

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Characterization of Chemical Impurities in Glutaraldehyde

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116723 ◽

1975 ◽

Vol 33 ◽

pp. 620-621

Author(s):

B. J. Grenon ◽

A. J. Tousimis

Keyword(s):

Glutaric Acid ◽

Spectroscopic Analysis ◽

Aldol Condensation ◽

Condensation Product ◽

Amorphous Solid ◽

Water Soluble ◽

Impurity Component ◽

Chemical Impurities ◽

Soluble Liquid

Ever since the introduction of glutaraldehyde as a fixative in electron microscopy of biological specimens, the identification of impurities and consequently their effects on biologic ultrastructure have been under investigation. Several reports postulate that the impurities of glutaraldehyde, used as a fixative, are glutaric acid, glutaraldehyde polymer, acrolein and glutaraldoxime.Analysis of commercially available biological or technical grade glutaraldehyde revealed two major impurity components, none of which has been reported. The first compound is a colorless, water-soluble liquid with a boiling point of 42°C at 16 mm. Utilizing Nuclear Magnetic Resonance (NMR) spectroscopic analysis, this compound has been identified to be — dihydro-2-ethoxy 2H-pyran. This impurity component of the glutaraldehyde biological or technical grades has an UV absorption peak at 235nm. The second compound is a white amorphous solid which is insoluble in water and has a melting point of 80-82°C. Initial chemical analysis indicates that this compound is an aldol condensation product(s) of glutaraldehyde.

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Elemental analysis of human erythrocytes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015318x ◽

1989 ◽

Vol 47 ◽

pp. 242-243

Author(s):

S. A. Livesey ◽

A. A. del Campo ◽

E. S. Griffey ◽

D. Ohlmer ◽

T. Schifani ◽

...

Keyword(s):

Sample Preparation ◽

Elemental Analysis ◽

Human Erythrocyte ◽

Spectroscopic Analysis ◽

Model System ◽

Human Erythrocytes ◽

List Type ◽

Chemical Fixation ◽

Ethanol Dehydration ◽

Lowicryl K4m

The aim of this study is to compare methods of sample preparation for elemental analysis. The model system which is used is the human erythrocyte. Energy dispersive spectroscopic analysis has been previously reported for cryofixed and cryosectioned erythrocytes. Such work represents the reference point for this study. The use of plastic embedded samples for elemental analysis has also been documented. The work which is presented here is based on human erythrocytes which have been either chemically fixed and embedded or cryofixed and subsequently processed by a variety of techniques which culminated in plastic embedded samples.Heparinized and washed erythrocytes were prepared by the following methods for this study :(1). Chemical fixation in 4% paraformaldehyde/0.25% glutaraldehyde/0.2 M sucrose in 0.1 M Na cacodylate, pH 7.3 for 30 min, followed by ethanol dehydration, infiltration and embedding in Lowicryl K4M at -20° C.

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Chromatographic and spectroscopic analysis of the fluorescent compounds derived from monosaccharides on HPTLC-NH2plates

JPC - Journal of Planar Chromatography - Modern TLC ◽

10.1556/jpc.15.2002.6.11 ◽

2002 ◽

Vol 15 (6) ◽

pp. 449-453 ◽

Cited By ~ 5

Author(s):

G. Grygierczyk ◽

Walter Fischer ◽

M. Sajewicz ◽

P. Kuś ◽

R. Wrzalik ◽

...

Keyword(s):

Spectroscopic Analysis ◽

Fluorescent Compounds

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A Peptoid with Extended Shape in Water

10.26434/chemrxiv.7552139 ◽

2019 ◽

Author(s):

Jumpei Morimoto ◽

Yasuhiro Fukuda ◽

Takumu Watanabe ◽

Daisuke Kuroda ◽

Kouhei Tsumoto ◽

...

Keyword(s):

Spectroscopic Analysis ◽

Dimensional Space ◽

Three Dimensional ◽

Biomolecular Recognition ◽

Biological Application ◽

New Class ◽

Proteolytic Resistance ◽

Pharmacokinetic Properties ◽

Optically Pure ◽

Three Dimensional Space

<div> <div> <div> <p>“Peptoids” was proposed, over decades ago, as a term describing analogs of peptides that exhibit better physicochemical and pharmacokinetic properties than peptides. Oligo-(N-substituted glycines) (oligo-NSG) was previously proposed as a peptoid due to its high proteolytic resistance and membrane permeability. However, oligo-NSG is conformationally flexible and is difficult to achieve a defined shape in water. This conformational flexibility is severely limiting biological application of oligo-NSG. Here, we propose oligo-(N-substituted alanines) (oligo-NSA) as a new peptoid that forms a defined shape in water. A synthetic method established in this study enabled the first isolation and conformational study of optically pure oligo-NSA. Computational simulations, crystallographic studies and spectroscopic analysis demonstrated the well-defined extended shape of oligo-NSA realized by backbone steric effects. The new class of peptoid achieves the constrained conformation without any assistance of N-substituents and serves as an ideal scaffold for displaying functional groups in well-defined three-dimensional space, which leads to effective biomolecular recognition. </p> </div> </div> </div>

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