Staining Flashcards
Nucleus/nucleic acid affinity
Basic stains
Cytoplasm (basic) affinity
Acidic stains
Direct interaction w/ a dye or staining solution
Histologic staining
For hemosiderin (ferric iron) Deep blue color
Perl’s prussian blue
Stains glycogen, mucoproteins, hyaline casts, glomerular basement membrane
Color magenta
Periodic acid schiff
Uses aqueous or alcoholic dye solutions (e.g. methylene blue, eosin) to produce a color
Direct staining
Uses a mordant or another agent to intensify the action of the dye used
Ex: gram stain, hematoxylin
Indirect staining
Serves as a link/bridge b/w the tissue & the dye
Ex:
potassium alum w/ hematoxylin in Ehrlich’s hematoxylin
Iron in weigert’s hematoxylin
Mordant
Insoluble tissue mordant dye complex
Dye + mordant
Hastens the staining rxn by ⬆️ the staining power & selectivity of the dye
Ex:
Potassium hydroxide in loeffler’s methylene blue
Phenol in carbol thionine & carbol fuchsin
Accentuator
No over staining
Tissue elements are stained in definite sequence
No decolorizer is applied
Progressive staining
Overstaining is done
Regressive staining
Selective removal of excess stain so that a specific substance may stain distinctly from the surrounding tissue
Ex: acid alcohol
Decolorizer
Staining w/ a color that is different from that of the stain itself All are cationic or basic dyes belonging to thizine & triphenylmethane groups Ex: Methyl violet Bismarck brown Methylene blue Toluidine blue Cresyl blue
Metachromatic staining
Important in metachromatic staining
Water
Tends to lose the metachromatic stain
Alcohol
For contrast & background
Counterstaining
Most common counter stain
Eosin
Red cytoplasmic stains (EEP)
Eosin y
Eosin b
Phloxine b
Yellow cytoplasmic stains (POR)
Picric acid
Orange g
Rose bengal
Green cytoplasmic stains (LL)
Light green sf
Lissamine green
Red nuclear stains (NSCH)
Neutral red
Safranin o
Carmine
Hematoxylin
Blue nuclear stains (MTC)
Methylene blue
Toluidine blue
Celestine blue
Demonstration of tissue elements using solutions of metallic salts that are deposited on the tissue surface
Metallic impregnation
The selective staining of living cell constituents
Vital stains
Resistant to vital stains
Staining of this indicates cell is already dead
Nucleus
Type of vital staining by injecting the dye into any part of the animal body Ex: Lithium Carmine India ink
Intravital staining
Type of vital staining where it is used immediately after removal of cells from the living body Ex: Neutral red Janus green Trypan blue Nile blue Thionine Toluidine blue
Supravital staining
Best vital dye
Neutral red
Natural dye obtained from hematoxylin campechianum: mexican tree
Hematoxylin
Active coloring in hematoxylin
Hematin
Extracted from coccus cacti: female cochineal bug
Cochineal dyes
Demonstration of glycogen: highly specific
Bright red color
Best’s carmine
Extracted from lichens
Used for staining elastic fibers of skin
Also the source of litmus paper
Aka taenzer unna method
Orcein
Aka coal tar dyes or aniline dyes
Derived from hydrocarbon benzene
Synthetic dyes
Substances w/ definite atomic groupings that are capable of producing visible color but not permanent
Chromophore
Simple benzene compounds that contain chromophores
Chromogens
Substances that are added to a chromogen w/c alters the property of the chromogen by altering its shade, enabling it to form salts w/ another compound & enables it to retain its color in the tissue
Auxochrome
Impart color that is permanent
Chromophore + auxochrome
Dyes
Most commonly used for histologic studies
Filtered prior to use
Hematoxylin
Example of aluminum hematoxylin
Routinely used in nuclear staining
Harris hematoxylin
Excellent nuclear stain
Stains mucin
Recommended for bone & cartilage
Glycerin added to slow oxidation & to prolong shelf life of hematoxylin
Ehrlich’s hematoxylin
Most commonly used eosin
Soluble in water
Green yellow fluorescence
Eosin y
Deeper red color form of eosin
Eosin b, erythrosin b
Eosin form soluble in alcohol
Eosin s, ethyl eosin
For demonstration of connective tissues ➡️ collagen fibers
Simplest method
Van gieson’s stain
Green fluorescence in acridine orange
Dna
Red fluorescence in acridine orange
Rna
Most popular method for acid mucins
Blue color
Alcian blue
Carcinogenic
For staining hemoglobin
In fobt
Benzidine
Used as counterstain for gram’s technique, acid fast, pap’s
Used for staining diphtheria organisms
Bismarck brown
Best known as an indicator
Stains elastic tissues, amyloid, myelin
Congo red