3 Which chemical(s) is not used for staining cella?
Answers
Answer:
Staining is a technique used to enhance contrast in samples, generally at the microscopic level. Stains and dyes are frequently used in histology (the study of tissue under the microscope) and in the medical fields of histopathology, hematology, and cytopathology that focus on the study and diagnoses disease at a microscopic level. Stains may be used to define biological tissues (highlighting, for example, muscle fibers or connective tissue), cell populations (classifying different blood cells), or organelles within individual cells.
In biochemistry it involves adding a class-specific (DNA, proteins, lipids, carbohydrates) dye to a substrate to qualify or quantify the presence of a specific compound. Staining and fluorescent tagging can serve similar purposes. Biological staining is also used to mark cells in flow cytometry, and to flag proteins or nucleic acids in gel electrophoresis.
Staining is not limited to biological materials, it can also be used to study the structure of other materials for example the lamellar structures of semi-crystalline polymers or the domain structures of block copolymers.
Contents
1 In vivo vs In vitro
2 Microscopy in Staining
3 Preparation
3.1 Standardization
3.2 Negative staining
3.3 Positive staining
3.4 Simple Staining versus Differential Staining
3.5 Types of Staining Techniques[7]
4 Specific techniques
4.1 Gram staining
4.2 Endospore staining
4.3 Ziehl-Neelsen stain
4.4 Haematoxylin and eosin (H&E) staining
4.5 Papanicolaou staining
4.6 PAS staining
4.7 Masson's trichrome
4.8 Romanowsky stains
4.9 Silver staining
4.10 Sudan staining
4.11 Wirtz-Conklin staining
4.12 Collagen Hybridizing Peptide Staining
5 Common biological stains
5.1 Acridine orange
5.2 Bismarck brown
5.3 Carmine
5.4 Coomassie blue
5.5 Cresyl violet
5.6 Crystal violet
5.7 DAPI
5.8 Eosin
5.9 Ethidium bromide
5.10 Acid fuchsin
5.11 Haematoxylin
5.12 Hoechst stains
5.13 Iodine
5.14 Malachite green
5.15 Methyl green
5.16 Methylene blue
5.17 Neutral red
5.18 Nile blue
5.19 Nile red
5.20 Osmium tetroxide (formal name: osmium tetraoxide)
5.21 Propidium Iodide
5.22 Rhodamine
5.23 Safranine
6 Stainability of tissues
7 Electron microscopy
7.1 Phosphotungstic acid
7.2 Osmium tetroxide
7.3 Ruthenium tetroxide
8 See also
9 References
10 Further reading
11 External links
In vivo vs In vitro
In vivo staining (also called vital staining or intravital staining) is the process of dyeing living tissues. By causing certain cells or structures to take on contrasting colour(s), their form (morphology) or position within a cell or tissue can be readily seen and studied. The usual purpose is to reveal cytological details that might otherwise not be apparent; however, staining can also reveal where certain chemicals or specific chemical reactions are taking place within cells or tissues.
In vitro staining involves colouring cells or structures that have been removed from their biological context. Certain stains are often combined to reveal more details and features than a single stain alone. Combined with specific protocols for fixation and sample preparation, scientists and physicians can use these standard techniques as consistent, repeatable diagnostic tools. A counterstain is stain that makes cells or structures more visible, when not completely visible with the principal stain.
Crystal violet stains both Gram positive and Gram negative organisms. Treatment with alcohol removes the crystal violet colour from gram negative organisms only. Safranin as counterstain is used to colour the gram negative organisms that got decolorised by alcohol.
While ex vivo, many cells continue to live and metabolize until they are "fixed". Some staining methods are based on this property. Those stains