On structural formulas of basic fuchsin and aldehyde-schiff reaction products

1975 ◽  
Vol 45 (4) ◽  
pp. 255-265 ◽  
Author(s):  
Holde Puchtler ◽  
Susan N. Meloan ◽  
Barbara R. Brewton
Keyword(s):  
Reaction Products ◽  
Basic Fuchsin ◽  
Structural Formulas ◽  
Schiff Reaction

scholarly journals THE PERIODATE-SCHIFF REACTION: SPECIFICITY, KINETICS, AND REACTION PRODUCTS WITH PURE SUBSTRATES

1965 ◽  
Vol 13 (6) ◽  
pp. 423-430 ◽  
Author(s):  
ARNE DAHLQVIST ◽  
INGE OLSSON ◽  
ÅKE NORDÉN
Keyword(s):  
Nucleic Acids ◽  
Simple Relation ◽  
Test Tube ◽  
Reaction Products ◽  
Chromatographic Mobility ◽  
Reaction Specificity ◽  
Rate Of Reaction ◽  
Pure Substances ◽  
Schiff Reaction ◽  
Aldehyde Groups

A quantitative test-tube method has been used to study the periodate-Schiff reaction of a number of pure substances. The rate of reaction, the amount of color produced, and in some cases the amount of periodate consumed, have been measured. The dye produced by different carbohydrates has been analyzed by spectrophotometry and paper chromatography. Glycogen, starch and dextran reacted slowly and produced much less color than the corresponding amount of free monosaccharides. Oligosaccharides and heteropolysaccharides were either periodate-Schiff-negative or very weakly positive. Proteins and nucleic acids were negative. There was no simple relation between the intensity of the periodate-Schiff reaction and the amount of periodate consumed or the amount of aldehyde groups formed on the oxidation by periodate. The dyes formed with different carbohydrates had essentially the same absorption curve, but differed in their chromatographic mobility.

scholarly journals The influence of chromatin compactness on the stoichiometry of the Feulgen-Schiff procedure studied in model films. II. Investigations on films containing condensed or swollen chicken erythrocyte nuclei.

1975 ◽  
Vol 23 (12) ◽  
pp. 891-900 ◽  
Author(s):  
W A Duijndam ◽  
P van Duijn
Keyword(s):  
Staining Intensity ◽  
Nuclear Material ◽  
Reaction Products ◽  
Chromatin Compactness ◽  
High Reduction ◽  
Protein Components ◽  
Schiff Reaction ◽  
Chicken Erythrocytes ◽  
Aldehyde Groups ◽  
Very High

As models for different states of chromatin compactness, nuclei from chicken erythrocytes were isolated and either osmotically swollen or kept as condensed as possible. Both types of nuclei were then fixed and incorporated into polyacrylamide films. Hydrolysis with 5 N HCl and staining with Schiff's reagent of these model films were studied using several parameters. The phosphate content of the films was analyzed as a parameter for the depolymerization losses and the staining with Schiff's reagent as a parameter for the apurinic acid (APA) content. The loss of ultraviolet absorbance from the films and the accumulation of ultraviolet absorbing substances in the hydrolyzing acid were monitored as parameters for the progress of hydrolysis. Conversion of the generated aldehyde groups to APA-Schiff chromophore is shown to take place with the same stoichiometry for both types of nuclei as well as for DNA in model films. It is further shown that the nuclei- and DNA-films are suitable models for investigating the influence of chromatin compactness on the course of the Feulgen-Schiff reaction. For the most compact form of chromatin studied, a very high reduction in staining intensity of up to 40% could be demonstrated after certain normally applied hydrolysis times. This is due primarily to a decrease with a factor of 2.3 of the depurination rate constants of these models (from 0.030/min to 0.013/min). Therefore prolonged hydrolysis periods are required to obtain the same APA concentrations, but then depolymerization processes cause losses of nuclear material. The differences in depurination rates could be explained by a decrease in [H3O]+ in the neighborhood of the purine-sugar linkages, caused by the presence of fixed positive charges form the protein components of the chromatin. These findings may explain the cytophotometrically determined differences in chromophore yield of 10-20% found in the nuclei of cells with different states of compactness of their chromatin. The descending part of the Feulgen hydrolysis curve represents the depolymerization of APA and loss by diffusion of the reaction products. In the Appendix, cytophotometric data of cells have been analyzed to show that this part of the hydrolysis curve may be used to estimate the acid stability of chromatin complexes. The depurination and depolymerization rates found closely correspond with the data obtained from the model films.

The Histochemical Demonstration of Keratin by Methods involving Selective Oxidation

1951 ◽  
Vol s3-92 (20) ◽  
pp. 393-402
Author(s):  
A. G. EVERSON PEARSE
Keyword(s):  
Periodic Acid ◽  
Cobalt Nitrate ◽  
Histochemical Demonstration ◽  
Performic Acid ◽  
Cysteic Acid ◽  
Acid Oxidation ◽  
Reaction Products ◽  
Periodic Acid Schiff ◽  
Periodic Acid Oxidation ◽  
Schiff Reaction

1. Oxidation of tissues with performic acid gives rise to histochemically detectable reaction products particularly in two classes of material. These are keratin and lipoids of the phosphatide class. 2. Three methods have been evolved for visualizing the effect of performic acid on cystine-containing structures; two of these (performic acid/Schiff and perfoiTnic acid/cobalt nitrate) also record the effect on lipoids. 3. An attempt has been made to elucidate the chemistry of the reactions and it is suggested that oxidation of cystine in the tissues gives rise not only to cysteic acid (alanine-beta-sulphonic) but to another acid (alanine-beta-sulphinic). The latter is responsible for the positive reaction with Schiff's solution. 4. The Schiff reaction with performic acid oxidized lipoids is due to the formation of substances giving the reactions of aldehydes. It is possible that similar groups may be produced from lipoid molecules by periodic acid oxidation and that these and not polysaccharides (1.2 glycols) are responsible for the periodic acid-Schiff reaction in such cases.

A Silver-Schiff Reaction for Cytological Studies: Light Microscope Observations

1964 ◽  
Vol s3-105 (71) ◽  
pp. 363-366
Author(s):  
JOHN H. D. BRYAN
Keyword(s):  
Metal Ion ◽  
Deoxyribonucleic Acid ◽  
Metallic Silver ◽  
Basic Fuchsin ◽  
Cytoplasmic Staining ◽  
Specific Manner ◽  
Tissue Lipids ◽  
Schiff Reaction ◽  
Plasmal Reaction ◽  
Ammoniacal Silver

A method is presented in which a complex metal-ion (ammoniacal silver) is substituted for leuco-basic fuchsin in the well-known Schiff reaction for aldehydes. The reagent is reduced to metallic silver by tissue aldehydes and submicroscopic particles of the metal are deposited at the reactive sites. When the reagent is used in the Feulgen reaction chromosomes may be ‘stained’ in a specific manner to show the localization of deoxyribonucleic acid. For such a purpose, fixation should be carried out with acetic acid and alcohol mixtures rather than with solutions containing formalin or dichromate; these latter substances preserve more of the tissue lipids and thus complicate the issue by producing cytoplasmic staining (plasmal reaction).

Lead aspartate: a new en bloc stain for electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 34-35
Author(s):  
J.R. Walton
Keyword(s):  
Electron Microscopy ◽  
Calcium Ion ◽  
Enzyme Reaction ◽  
Lead Citrate ◽  
Reaction Products ◽  
En Bloc ◽  
Thin Sections ◽  
Lead Salts ◽  
Thin Sectioning ◽  
High Alkalinity

In electron microscopy, lead is the metal most widely used for enhancing specimen contrast. Lead citrate requires a pH of 12 to stain thin sections of epoxy-embedded material rapidly and intensively. However, this high alkalinity tends to leach out enzyme reaction products, making lead citrate unsuitable for many cytochemical studies. Substitution of the chelator aspartate for citrate allows staining to be carried out at pH 6 or 7 without apparent effect on cytochemical products. Moreover, due to the low, controlled level of free lead ions, contamination-free staining can be carried out en bloc, prior to dehydration and embedding. En bloc use of lead aspartate permits the grid-staining step to be bypassed, allowing samples to be examined immediately after thin-sectioning.Procedures. To prevent precipitation of lead salts, double- or glass-distilled H20 used in the stain and rinses should be boiled to drive off carbon dioxide and glassware should be carefully rinsed to remove any persisting traces of calcium ion.

Otoconia formation in the chick embryo

1983 ◽  
Vol 41 ◽  
pp. 572-573
Author(s):  
C.D. Fermin ◽  
M. Igarashi
Keyword(s):  
Chick Embryo ◽  
Inner Ear ◽  
Gallus Domesticus ◽  
The Body ◽  
Abnormal Behavior ◽  
Intensive Study ◽  
Basic Fuchsin ◽  
Gestational Period ◽  
Sensory Epithelia ◽  
Transmission Electron

Otoconia are microscopic geometric structures that cover the sensory epithelia of the utricle and saccule (gravitational receptors) of mammals, and the lagena macula of birds. The importance of otoconia for maintanance of the body balance is evidenced by the abnormal behavior of species with genetic defects of otolith. Although a few reports have dealt with otoconia formation, some basic questions remain unanswered. The chick embryo is desirable for studying otoconial formation because its inner ear structures are easily accessible, and its gestational period is short (21 days of incubation).The results described here are part of an intensive study intended to examine the morphogenesis of the otoconia in the chick embryo (Gallus- domesticus) inner ear. We used chick embryos from the 4th day of incubation until hatching, and examined the specimens with light (LM) and transmission electron microscopy (TEM). The embryos were decapitated, and fixed by immersion with 3% cold glutaraldehyde. The ears and their parts were dissected out under the microscope; no decalcification was used. For LM, the ears were embedded in JB-4 plastic, cut serially at 5 micra and stained with 0.2% toluidine blue and 0.1% basic fuchsin in 25% alcohol.

Studies of Oxide Formation on Copper Thin Films by Electron Microscopy

1977 ◽  
Vol 35 ◽  
pp. 316-317
Author(s):  
G. G. Hembree ◽  
M. A. Otooni ◽  
J. M. Cowley
Keyword(s):  
Electron Microscopy ◽  
Electron Diffraction ◽  
Single Crystal ◽  
Crystal Surface ◽  
Crystal Defects ◽  
Diffraction Reflection ◽  
Reaction Products ◽  
Intermediate Energies ◽  
Crystal Films ◽  
Reflection Electron Microscopy

The formation of oxide structures on single crystal films of metals has been investigated using the REMEDIE system (for Reflection Electron Microscopy and Electron Diffraction at Intermediate Energies) (1). Using this instrument scanning images can be obtained with a 5 to 15keV incident electron beam by collecting either secondary or diffracted electrons from the crystal surface (2). It is particularly suited to studies of the present sort where the surface reactions are strongly related to surface morphology and crystal defects and the growth of reaction products is inhomogeneous and not adequately described in terms of a single parameter. Observation of the samples has also been made by reflection electron diffraction, reflection electron microscopy and replication techniques in a JEM-100B electron microscope.A thin single crystal film of copper, epitaxially grown on NaCl of (100) orientation, was repositioned on a large copper single crystal of (111) orientation.

Precipitation in silicon: Microanalysis

1988 ◽  
Vol 46 ◽  
pp. 474-475
Author(s):  
R.W. Carpenter
Keyword(s):  
Transition Metals ◽  
Spatial Resolution ◽  
Thin Foil ◽  
Precipitation Reaction ◽  
High Current ◽  
Reaction Products ◽  
Carbon And Nitrogen ◽  
Dielectric Layers ◽  
Precipitation Processes ◽  
Areas Of Interest

Interest in precipitation processes in silicon appears to be centered on transition metals (for intrinsic and extrinsic gettering), and oxygen and carbon in thermally aged materials, and on oxygen, carbon, and nitrogen in ion implanted materials to form buried dielectric layers. A steadily increasing number of applications of microanalysis to these problems are appearing. but still far less than the number of imaging/diffraction investigations. Microanalysis applications appear to be paced by instrumentation development. The precipitation reaction products are small and the presence of carbon is often an important consideration. Small high current probes are important and cryogenic specimen holders are required for consistent suppression of contamination buildup on specimen areas of interest. Focussed probes useful for microanalysis should be in the range of 0.1 to 1nA, and estimates of spatial resolution to be expected for thin foil specimens can be made from the curves shown in Fig. 1.

TEM characterization of reaction zone in a SiC fiber-reinforced titanium alloy

1988 ◽  
Vol 46 ◽  
pp. 738-739
Author(s):  
G. Das ◽  
R. E. Omlor
Keyword(s):  
Titanium Alloys ◽  
Reaction Zone ◽  
Carbon Layer ◽  
Fiber Reinforced ◽  
Reaction Products ◽  
Sic Fibers ◽  
Sic Fiber ◽  
The Matrix ◽  
Immense Potential

Fiber reinforced titanium alloys hold immense potential for applications in the aerospace industry. However, chemical reaction between the fibers and the titanium alloys at fabrication temperatures leads to the formation of brittle reaction products which limits their development. In the present study, coated SiC fibers have been used to evaluate the effects of surface coating on the reaction zone in the SiC/IMI829 system.IMI829 (Ti-5.5A1-3.5Sn-3.0Zr-0.3Mo-1Nb-0.3Si), a near alpha alloy, in the form of PREP powder (-35 mesh), was used a茸 the matrix. CVD grown AVCO SCS-6 SiC fibers were used as discontinuous reinforcements. These fibers of 142μm diameter contained an overlayer with high Si/C ratio on top of an amorphous carbon layer, the thickness of the coating being ∽ 1μm. SCS-6 fibers, broken into ∽ 2mm lengths, were mixed with IMI829 powder (representing < 0.1vol%) and the mixture was consolidated by HIP'ing at 871°C/0. 28GPa/4h.

Microstructural and fractographic characterization of B4C-Al cermets tested under dynamic and static loading

1989 ◽  
Vol 47 ◽  
pp. 562-563
Author(s):  
Gyeung Ho Kim ◽  
Mehmet Sarikaya ◽  
D. L. Milius ◽  
I. A. Aksay
Keyword(s):  
Thin Film ◽  
Mechanical Properties ◽  
Fracture Toughness ◽  
Static Loading ◽  
Carbon Deposition ◽  
Full Density ◽  
Unique Combination ◽  
Strong Component ◽  
Reaction Products

Cermets are designed to optimize the mechanical properties of ceramics (hard and strong component) and metals (ductile and tough component) into one system. However, the processing of such systems is a problem in obtaining fully dense composite without deleterious reaction products. In the lightweight (2.65 g/cc) B4C-Al cermet, many of the processing problems have been circumvented. It is now possible to process fully dense B4C-Al cermet with tailored microstructures and achieve unique combination of mechanical properties (fracture strength of over 600 MPa and fracture toughness of 12 MPa-m1/2). In this paper, microstructure and fractography of B4C-Al cermets, tested under dynamic and static loading conditions, are described.The cermet is prepared by infiltration of Al at 1150°C into partially sintered B4C compact under vacuum to full density. Fracture surface replicas were prepared by using cellulose acetate and thin-film carbon deposition. Samples were observed with a Philips 3000 at 100 kV.

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