safranin造句

• Commercial safranin preparations often contain a blend of both types.
• Both compounds behave essentially identically in biological staining applications, and most manufacturers of safranin do not distinguish between the two.
• The Chlamydiaceae and Mycoplasmataceae lack a peptidoglycan layer so do not retain crystal violet or safranin, resulting in no color.
• Safranin typically has the chemical structure shown at right ( sometimes described as "'dimethyl safranin "').
• Safranin typically has the chemical structure shown at right ( sometimes described as "'dimethyl safranin "').
• During the staining process, " E . coli " picks up the color of the counterstain safranin and stains pink.
• Counterstain, which is usually positively charged safranin or basic fuchsine, is applied last to give decolorized gram-negative bacteria a pink or red color.
• Gram-negative bacteria have a thin peptidoglycan layer which does not retain the crystal violet, so when safranin is added during the process, they stain red.
• Also in Gram staining, crystal violet stains only Gram-positive bacteria, and safranin counterstain is applied which stains all cells, even allowing the identification of Gram-negative bacteria as well.
• Their peptidoglycan layer is much thinner and sandwiched between an inner cell membrane and a bacterial outer membrane, causing them to take up the counterstain ( safranin or fuchsine ) and appear red or pink.
• Gram staining uses two dyes : Crystal violet and Fuchsin or Safranin ( the counterstain ) to differentiate between Gram-positive bacteria ( large Peptidoglycan layer on outer surface of cell ) and Gram-negative bacteria.
• Other compounds used to color tissue sections include safranin, Oil Red O, Congo red, Fast green FCF, silver salts, and numerous natural and artificial dyes that usually originated from the development of dyes for the textile industry.
• Gram-positive bacteria retain the crystal violet dye, and thus are stained violet, while the Gram-negative bacteria do not; after washing, a counterstain is added ( commonly safranin or fuchsine ) that will stain these Gram-negative bacteria a pink color.