. Appendix 4.6. using silanised silica gel G as the coating substance and a mixture of 2 volumes of methanol and 1 volume of water as the mobile phase

5 mg with 10ml of water for 1 minute and add 03 ml of ferric chloride solution, an intense green colour Is produced, which quickly becomes reddish brown.E Suspend 20 mg In 5 ml of water and add 6 ml of cupri-Tartaric solution and heal, the colour of the solution changes to dark brown and a red precipitate is produced. Clarity and colour of solution Dissolve 025 g in 25 ml of IM hydrochloric acid The solution Is clear, Appendx 6 1, and not more Intensely coloured than reference solution BYSS or BS6. Appendix 6.2.Specific optical rotation Between 22.5° and 26.5°, determined in a solution prepared by dissolving 025 g in 25 ml of aluminium chloride solution. Appendix 8.9 Heavy metals. Not more lhan 20 ppm, determined on 1.0 g by Method B. Appendx 3.12 Hydrazine Carry out the method for thin-layer chromatography. Appendix 4.6. using silanised silica gel G as the coating substance and a mixture of 2 volumes of methanol and 1 volume of water as the mobile phase Apply separately to the plate 10 pi ol each of The following solutions For solution (1) place 25 g ol strongly basic anlon exchange resin into each ol two stoppered conical flasks, add 150 ml of carbon dioxide -free water to each flask and allow to stand for 30 minutes shaking occasionally. Decant the liquid from both flasks and repeal the process with further quantities, each of 150 ml of carbon doxide-free water Separately, transfer the resin portions into two 100-ml measuring cylinders. 3.5 to 4.5 cm in internal diameter, using 60 ml of carton doxide-free water for one portion (A) and 20 ml of carbon dioxide free water for the other portion (B). Info each cylinder. Insert a gas-Inlet lube, 2 to 3 mm In internal diameter at the end and reaching almost to the bottom of the cylinder.and pass a rapid current of nitrogen for chromatography through each mixture so that homogeneous suspensions are produced. After 30 minutes, without interrupting The gas How, add 1 ml of a solution prepared by dissolving 05 g of the substance being examined in sufficient 2M hydrochloric acid to produce 2 ml to cylinder A After 1 minute stop the gas flow to cylinder A and transfer the contents, through a moistened filter paper, into cylinder B After 1 minute, stop the gas How to cylinder B and immedaiety pour the solution through a moistened filter paper into a freshly prepared mixture of 1 ml of a 20% w/v solution of salicylaldehyde in methanol and 20 ml of phosphate buffer solution pH 5.5, shake thoroughly for 1 minute and heat in a water-bath at 60* for 15 minutes; the liquid becomes clear Allow to cool, add 2 ml-of toluene, shake vigorously for 2 minutes and centrifuge Vigorously shake the toluene layer with Two quantities, each of 20 ml. of a 20% w/v solution of sodum melabisulphite and then with two quantities, each of 50 ml, of water and use The toluene layer Prepare solution (2) at The same lime and in the same manner cut using 1 ml of a O.OC00 w/v solution of hydrazine sulphate in 2M hydrochloric acid In place of 1 mf of the solution of the substance being examined After removal of the plate, allow it to cry in air and examine under ultra-violet light (365 nm). Any secondary spot In the chromalogram obtained with solution (1) showing a yellow fluorescence is not more intense than the correspondng spot In the chromatogram obtained with solution (2) Meihyldopa and 3-O-methylcarbidopa Carry out the method for high performance liquid chromatography. Appendix 4 3, using the following