Staining Prussian blue

The uptake if iron often requires Fe(II) as the bioavailable form, and uptake from soils containing insoluble Fe(III) is accomplished by phenolic compounds which are exuded by certain plants (Chaney and Bell, 1987). A particular use of staining has been in the study of the sites if iron reduction in plants, using Prussian blue stain (PB) (Ambler et al., 1971 Brown and Ambler, 1974). The method consists of placing the roots in a nutrient solution containing Fe(III) and ferricyanide. Since PB can be produced both from Fe(III) and Fe(CN)64 and from Fe(II) and Fe(CN)63, reduction of either source of iron in the presence of the roots will produce PB at the sites of... 

Fe reduction. Sections of roots can then be viewed under the microscope and the stain located. Bell et al. (1988) have evaluated the use of ferricyanide and the use of nitro-BT, [2,2 -di-/>-nitro-phenyl-5,5 -diphenyl]-3,3 -(3,3 -dimethoxy-4,4 -biphenylene)-di-tetrazolium chloride. With ferricyanide, iron-stressed tomato plants were mainly stained on the younger roots hairs located on the laterals or primary root tip. Nitro-BT is thought to compete with Fe(III) at the same transmembrane ferric reduction site (Sijmons and Bienfate, 1983). A purple diformazan precipitate is produced on reduction. Although the roots were stained in a similar way to those incubated with ferricyanide, Bell et al. (1988) point out that further research is required to determine if nitro-BT reduction completes with ferric reduction at the same site in the tomato. The iron-stress redox activity has been shown to be localised on the plasma membrane in tomato roots (Buckout et al., 1989), and electron microscopic examination (see next section) of the roots stained with Prussian blue indicated that the PB had accumulated between the plasma membrane and the cell walls of the root hairs and epidermal cells (Wergin et al., 1988). 

FIGURE 12.69 The neoplastic mesothelial cells showed abundant intracytoplasmic hemosiderin as demonstrated in this Prussian-Blue iron stained section. X 200. 

Decreased bone marrow iron on Prussian blue stains... 

Price-Butler method = Prussian blue method Reduction of ferric to ferrous ions followed by formation of the hexacyanoferrate-(l 1 )-chelate (Prussian blue). detection wavelength 720 nm complexes are unstable (precipitates), cuvettes become stained, timed addition of FeClj (instability ), sensitivity toward flavanols < I0 4 M, use of Prussian blue standard, number of reduced moles of ferric ions can be calculated 58,109... 

Studies in weaning rats, in which the spleen was stained with the Prussian blue technique, indicate that the uptake of hemosiderin by splenic macrophage does not occur until adult-age histological development is achieved (58-60 days postpartum). Moreover, the ability of the spleen macrophage to store iron increases with the age of the animal. 

Haleys Dialyzed Iron and Related Methods, Hyaluronic acid was said by Hale to combine with dialyzed iron in acetic acid solution 89), After the sections were rinsed, the classical HCl - potassium ferrocyanide reaction was used to color (as Prussian blue) the sites of iron-binding. The need for fixatives that would not dissolve hyaluronic acid was emphasized. The specificity was established by exposing duplicate portions of tissue to streptococcal hyaluronidase, presumable filtrates, before staining. This prevented coloration of hyaluronic acid but not that of other acidic carbohydrates. 

Prussian Blue pre-shon- n [Prussia, Germany] (1724) Brilliant deep blue pigment of excellent staining power, good lightfastness, but unstable in the presence of alkalis. It is usually obtained as a very fine powder. Its oil absorption is about 90. See Iron Blue. Syn ... 

A form of Prussian blue (q.v.) supplied in pulp form, without drying, for paper staining and the preparation of water paints (Heaton, 1928). 

Fig. 2 In vivo MRI of rabbit ischemic brain that received mesenchymal stem cells labeled with chitosan-SPION. Asterisk indicates ischemic area and open arrows indicate chitosan-SPION-labeled mesenchymal stem cells at the injection site, (a, b) T2WI and diffusion weighted image (DWI) of brain immediately after injection of mesenchymal stem cell at contralateral side of ischemic area (open arrows) on day 4 of ischemia, (c, d) T2WI and susceptibility weighted image (SWI) 16 days after stem cell transplantation. At the ischemic site, dark signal (white arrows) on SWI matches mesenchymal stem cells (black arrows) on Prussian staining (e, f)- (e. 0 Prussian blue staining detected iron-labeled stem cells at the liquefied infarct area in a section of 4% paraformaldehyde-fixed brain tissue tut day 16. Reprinted fiom [92] by permission fi om The Korean Academy of Medical Sciences, Journal of Korean Medical Science. Copyright 2010...

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