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In hemocytometry, Türk's solution (or Türk's fluid) is a hematological stain (either crystal violet or aqueous methylene blue) prepared in 99% acetic acid (glacial) [1] and distilled water. The solution destroys the red blood cells and platelets within a blood sample (acetic acid being the main lyzing agent ), and stains the nuclei of the ...
Incubation times for optimum staining varies from compound to compound. UV-excited dyes can require an hour or more while blue-light-excited dyes require a mere 15 minutes. [24] Staining can be accompanied by buffers such as Triton X-100 which make cells more permeable to stains. They are especially used in cell-impermeant dyes like TO-PRO-1.
Research has since been conducted on "tadpoling", which is a variation of "frogging" that is completed by keeping the test cells diluted in liquid throughout their examination. [ 1 ] A viability assay is an assay that is created to determine the ability of organs , cells or tissues to maintain or recover a state of survival. [ 2 ]
Determining the viable cell count is important for calculating dilutions required for the passaging of cells, as well as determining the size and number of flasks needed during growth time. It is also vital when seeding plates for assays, such as the plaque assay , [ 2 ] because the plates need a known number of live replicating cells for the ...
Gram-positive bacteria have a thick layer of peptidoglycan within the cell wall, and Gram-negative bacteria have a thin layer of peptidoglycan. Gram-positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured when seen through an optical microscope. This is because the thick layer of peptidoglycan ...
Gram staining differentiates bacteria by the chemical and physical properties of their cell walls. Gram-positive cells have a thick layer of peptidoglycan in the cell wall that retains the primary stain, crystal violet. Gram-negative cells have a thinner peptidoglycan layer that allows the crystal violet to wash out on addition of ethanol.
A Ziehl–Neelsen stain is an acid-fast stain used to stain species of Mycobacterium tuberculosis that do not stain with the standard laboratory staining procedures such as Gram staining. This stain is performed through the use of both red coloured carbol fuchsin that stains the bacteria and a counter stain such as methylene blue .
Crystal violet is also used as a tissue stain in the preparation of light microscopy sections. [15] In laboratory, solutions containing crystal violet and formalin are often used to simultaneously fix and stain cells grown in tissue culture to preserve them and make them easily