Phenylmercuric borate EUROPEAN PHARMACOPOEIA 7.0 Second identification: B, C. IDENTIFICATION A. Infrared absorption spectrophotometry (2.2.24). A. Infrared absorption spectrophotometry (2.2.24). Comparison: Ph. Eur. reference spectrum of Preparation:discs. phenylmercuric acetate. Comparison: Ph. Eur. reference spectrum of B. To 5 mL of solution S (see Tests) add 5 mL of water R and phenylmercuric borate. 0.1 mL of sodium sulfide solution R. A white precipitate is B. To 2 mL of solution S (see Tests) add 8 mL of water R and formed that darkens slowly on heating. 0.1 mL of sodium sulfide solution R. A white precipitate is C. To 10 mL of solution S add 2 mL of potassium iodide formed that darkens slowly on heating. solution R and shake vigorously. Filter. The filtrate gives C. Dissolve about 20 mg in 2 mL of methanol R.Thesolution reaction (b) of acetates (2.3.1). is clear and colourless. Ignite; the solution burns with a green-edged flame. TESTS Solution S. Dissolve 0.250 g in 40 mL of water R by heating to TESTS boiling. Allow to cool and dilute to 50 mL with water R. Prepare Solution S. Dissolve 0.25 g by sprinkling it on the surface of the solution immediately before use. 25 mL of boiling water R, cool and dilute to 25 mL with water R. Appearance of solution. Solution S is not more opalescent Appearance of solution. Solution S is clear (2.2.1)and than reference suspension II (2.2.1)andiscolourless(2.2.2, colourless (2.2.2, Method II). Method II). Ionised mercury:maximum0.01percent. Ionised mercury:maximum0.2percent. To 10 mL of solution S add 2 mL of potassium iodide solution R To 2 mL of solution S add 8 mL of water R,2mLofpotassium and 3 mL of dilute hydrochloric acid R. Filter. The filtrate is iodide solution R and 3 mL of dilute hydrochloric acid R. colourless. Wash the precipitate with 3 mL of water R.Combine Filter. The filtrate is not more coloured than the potassium thefiltrateandthewashings,add2mLofdilute sodium iodide solution used. Wash the precipitate with 3 mL of hydroxide solution R and dilute to 20 mL with water R.12mL water R. Combine the filtrate and the washings, add 2 mL of of this solution complies with test A for heavy metals (2.4.8). dilute sodium hydroxide solution R and dilute to 20 mL with Preparethereferencesolutionusingamixtureof2.5mLoflead water R. 12 mL of this solution complies with limit test A for standard solution (2 ppm Pb) R and 7.5 mL of water R. heavy metals (2.4.8). Prepare the standard using lead standard Loss on drying (2.2.32): maximum 3.5 per cent, determined on solution (1 ppm Pb) R. 0.50 g by drying in an oven at 45 °C for 15 h ± 30 min. Polymercuric benzene compounds:maximum1.5percent. ASSAY Shake 0.2 g with 10 mL of acetone R. Filter. Wash the residue twice with 5 mL of acetone R.Drytheresidueat105°Cfor1h. Mercury. Dissolve 0.300 g in 100 mL of water R and add 3 mL The residue weighs a maximum of 3 mg. of nitric acid R.Titratewith0.1 M ammonium thiocyanate, using 2 mL of ferric ammonium sulfate solution R2 as Loss on drying (2.2.32): maximum 0.5 per cent, determined on indicator, until a persistent reddish-yellow colour is obtained. 0.500gbydryinginanovenat45°Cfor15h. 1mLof0.1 M ammonium thiocyanate is equivalent to ASSAY 20.06 mg of Hg. Dissolve with heating 0.300 g in 100 mL of water R. Cool and Borates. Dissolve 0.600 g with heating in 25 mL of water R. add 3 mL of nitric acid R.Titratewith0.1 M ammonium Dissolve 10 g of sorbitol R in the hot solution and cool. Titrate thiocyanate using 2 mL of ferric ammonium sulfate solution R2 with 0.1 M sodium hydroxide,using0.5mLofphenolphthalein as indicator, until a persistent reddish-yellow colour is obtained. solution R as indicator, until a persistent pink colour is 1mLof0.1 M ammonium thiocyanate is equivalent to obtained. Carry out a blank titration. 33.67 mg of phenylmercuric acetate. 1mLof0.1 M sodium hydroxide is equivalent to 6.18 mg of H3BO3. STORAGE STORAGE Protected from light. Protected from light. 01/2008:0103 01/2008:0783 PHENYLMERCURIC BORATE PHENYLMERCURIC NITRATE Phenylhydrargyri boras Phenylhydrargyri nitras DEFINITION DEFINITION Compound consisting of equimolecular proportions of Mixture of phenylmercuric nitrate (C6H5HgNO3 ; Mr 339.7) and phenylmercuric orthoborate and phenylmercuric hydroxide phenylmercuric hydroxide (C6H5HgOH; Mr 294.7). (C12H13BHg2O4 ; Mr 633) or of the dehydrated form (metaborate, Content: 62.5 per cent to 64.0 per cent of Hg (Ar 200.6) (dried C12H11BHg2O3 ; Mr 615) or of a mixture of the 2 compounds. substance). Content: CHARACTERS — mercury (Hg; Ar 200.6): 64.5 per cent to 66.0 per cent (dried Appearance: white or pale yellow powder. substance), Solubility:veryslightlysolubleinwaterandinethanol(96per — borates expressed as H3BO3 : 9.8 per cent to 10.3 per cent cent), slightly soluble in hot water. It dissolves in glycerol and (dried substance). in fatty oils. CHARACTERS IDENTIFICATION Appearance: white or slightly yellowish, crystalline powder or A. To 5 mL of solution S (see Tests) add 8 mL of water R and colourless, shiny crystals. 0.1 mL of sodium sulfide solution R. A white precipitate is Solubility: slightly soluble in water and in ethanol (96 per cent). formed that darkens slowly on heating. 2716 See the information section on general monographs (cover pages).