Strontium citrate

Strontium citrate, an alternative oral treatment with proven efficacy. In laboratory experiments, strontium ranelate was shown to stimulate the proliferation of osteoblasts, as well as inhibit the proliferation of osteoclasts. 

Hastings AB, McLean FC, Eichelberger L, Hall JL, Da Costa E (1934) The ionization of calcium, magnesium, and strontium citrates. J Biol Chem 107 351-370 Whittier EO (1938) Buffer intensities of milk and milk constituents. III. Buffer action of calcium citrate. J Biol Chem 123 283-294... 

Hastings AB, McLean EC, Eichelberger JL, Da Costa E (1934) The ionization of calcium, magnesium and strontium citrates. J Biol Chem 107 351-370... 

Schubert J, Richter JW (1948) The use of ion exchangers for the determination of physical-chemical properties of substances, particularly radiotracers, in solution. II. The dissociation constants of strontium citrate and strontium tartrate. J Phys Chem 52 350-357 Schubert J, Lindenbaum A (1950) Complexes of calcium with citric acid and tricarballylic acids measured by ion exchange. Nature 166 913-914... 

OC-Hydroxycarboxylic Acid Complexes. Water-soluble titanium lactate complexes can be prepared by reactions of an aqueous solution of a titanium salt, such as TiCl, titanyl sulfate, or titanyl nitrate, with calcium, strontium, or barium lactate. The insoluble metal sulfate is filtered off and the filtrate neutralized using an alkaline metal hydroxide or carbonate, ammonium hydroxide, amine, or alkanolamine (78,79). Similar solutions of titanium lactate, malate, tartrate, and citrate can be produced by hydrolyzation of titanium salts, such as TiCl, in strongly (>pH 10) alkaline water isolation of the... 

Fluoride, in the absence of interfering anions (including phosphate, molybdate, citrate, and tartrate) and interfering cations (including cadmium, tin, strontium, iron, and particularly zirconium, cobalt, lead, nickel, zinc, copper, and aluminium), may be determined with thorium chloranilate in aqueous 2-methoxyethanol at pH 4.5 the absorbance is measured at 540 nm or, for small concentrations 0-2.0 mg L 1 at 330 nm. 

Baythoun, M. S. G Sale, F. R. 1982. Production of strontium-substituted lanthanum manganite perovskite powder by the amorphous citrate process. /. Mat. Sci. 17 2757-2769. 

Coprecipitation of the metals is usually achieved from an aqueous solution of nitrates upon addition of anions such as carbonates, citrates, or oxalates (10)(24-27). First reports in this field have underlined the necessity to neutralize the pH of the solution in order to obtain complete precipitation of barium or strontium. Also, oxalate or citrate ligands may bind to two different cations. This should allow a better mixing at a microscopic level. However, care should be taken since some cations such as Y or La may precipitate as double salt complexes with alkaline ions that have been added to the solution as hydroxides in order to control the pH (24). 

Metal salts may be used in the treatment of wool. Flame methods for the determination of aluminium [185], barium, chromium, copper, mercury, strontium, tin, zinc [186] and zirconium [187] in wool have been published. Standard additions to wool cleaned by soaking and washing it with disodium EDTA (800 ml of 0.5 M for 30g wool with soaking for 3 days and double washing) was used as the calibration technique. This compensated for interferences from hydrochloric acid and amino-acids. The samples were equilibrated to a constant humidity for 24 h and then 0.3 g sealed with 5 ml of constant boiling point hydrochloric acid in a glass tube. The tubes were placed in an oven at 110UC for 20 h. The nitrous oxide/acetylene flame was used for the determination of aluminium and zirconium. Sulphate, phosphate, citrate and silicate have been found to interfere in the determination of titanium and zirconium in fire-proofed wool [188], These flame... 

The problem of reducing sintering temperature is also crucial for Bao sSrg sTiOj, which possesses ferroelectric properties but is used more often as a material with a positive temperature coefficient of resistance (PTCR). The citrate synthesis method is often considered as an alternative to freeze-drying synthesis, but in the following case the solution of barium, strontium, and titanium citrates was dried by various methods (i.e., oven drying and freeze-drying). Careful... 

Aqueous potassium citrate solutions are slightly alkaline and will react with acidic substances. Potassium citrate may also precipitate alkaloidal salts from their aqueous or alcoholic solutions. Calcium and strontium salts will cause precipitation of the corresponding citrates. 

Chromatographic methods were also used out to analyse the relative amounts of °Sr and °Y in the separated "Y. Both the strontium and yttrium used were in the form of acetates. Paper chromatography was carried out using saline as the mobile phase, and paper electrophoresis was carried out using 30 cm Whatman No. 1 paper, 0.03M NaCl and 0.15 g/L sodium citrate at 500 V for 2 h. 

Complexones such as EDTA (complexone III) [1-3] and DCTA (complexone IV) [4,5] are suitable eluents, but other complexing agents, such as citrate [3,6] and sulphate [7] are also applied. Barium has been separated from strontium and other metals by cation-exchange chromatography using mixed HCl-organic solvent eluents [8]. Strontium has been enriched and determined in sea water [5] and in milk [2]. 

The metabolism of strontium consists of binding interactions with proteins and, based on its similarity to calcium, probably complex formation with various inorganic anions such as carbonate and phosphate, and carboxylic acids such as citrate and lactate (Alda and Escanero 1985 Inoue et al. 1988 Kshirsagar 1977 Lloyd 1968 Twardock et al. 1971). These types of interactions would be expected for all routes of exposure. These types of interactions would be expected for all routes of exposure including the following ... 

Metabolism. As noted in Section 3.4.3, the metabolism of strontium consists of binding interactions with proteins and probably complex formation with various inorganic anions such as carbonate and phosphate, and carboxylic acids such as citrate and lactate. 

Zander-Principati GE, Kuzma JF. 1964. Reduction of strontium-90 bone cancer by zirconium citrate. Int J Radiat Biol 8(5) 427-437. 

Ammonium citrate dibasic Barium fluoride Barium nitrate Bismuth Calcium fluoride Calcium titanate Carbon Cobalt sulfate (ous) Gold Hydrogen peroxide y-Linolenic acid Niobium oxide Nitrogen Palmitoleic acid Polyester carbonate resin Selenium Sodium chlorite Strontium titanate electronics applies. 

Strontium and vanadyl ions partially replace calcium activity by stimulating oxygen evolution after calcium depletion in pH 8.3 salt washed PS2, pH 3.0 citrate washed... 

Strontium radioisotopes in milk can be determined by making use of an ion exchange procedure. The milk sample is allowed to stand for 2 weeks to achieve a sufficient accumulation. Citrate and both yttrium and strontium carriers are added. The solution is applied onto a column of cation then anion exchangers. Strontium and yttrium are retained on the cation and anion exchangers, respectively. Yttrium is washed out from the anion exchanger with hydrochloric acid and precipitated as yttrium oxalate. After weighing the precipitate and determining the chemical yield the activity of the °Y is measured. In the presence of the yttrium oxalate is dissolved in concentrated nitric acid, and yttrium is extracted with tributyl phosphate. Lanthanum-140 remains in the aqueous phase. Yttrium is back-washed with nitric acid and precipitated as its oxalate. In an unfavorable case, i.e., when the amount of exceeds by several orders that of °Sr, the above separation procedure has to be repeated. 

The first agent to be authorized was strontium, but this also has a salty taste and is not compatible with fluorides. The next generation was strontium acetate, with a less salty taste, and better compatibility with fluoride. Potassium salts (chlorides, nitrates, citrates) are the most widely used today, as they are compatible with fluoride and they provide a neutral taste. 

Calcium that is protein-bound and inorganically complexed is detectable by FAAS only after dissociation fixim these complexes. Acid is used for the dissociation of protein-bound calcium and lanthanum or strontium ions are added, usually in the sample diluent, to displace calcium from phosphate, oxalate, citrate, and other complexes (10). Interference from magnesium and other elements is reduced by using a narrow bandpass, diffraction-grating spectrophotometer set at the specific absorption line of calcium (422.7 nm). Sodium and potassium interference is eliminated by the addition of physiological concentrations of sodium and potassium to the calcium standards (111-... 

Consequently, the amount of strontium available for exchange decreases as the animal ages. In old bone, the strontium finds its way either within the lattice defects or it is deposited in the form of new crystals in those areas where bone remodeling takes place. The mechanism of incorporation of radium in bone resembles that of strontium. The content in bone citrate will be discussed in the section on decalcification. 

Exchange among any of the four compartments is not limited to calcium and phosphate ions but may include any other species present in the bulk solution. Depending on the ion, it will be more or less concentrated in the hydration shell and will, or will not, be able to exchange with ions in the crystal lattice. Monovalent ions such as Na, F and K enter the hydration shell but do not become concentrated within it. Equilibrium is established between the ions in the bulk solution and those in the hydration shell. The polarizable ions include hydrated ions, especially multivalent ones, such as calcium, carbonate, citrate, magnesium and strontium, which, because of their ability to neutralize the surface charge on the crystals, tend to concentrate in the hydration shell where they are known as the bound ion layer. These ions are freely mobile, however, and can exchange readily with ions in the bulk solution. 

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