四环素胶囊--Tetracycline-Capsules-BP2009.pdfVIP

Browse: British Pharmacopoeia 2009 British Pharmacopoeia Volume III Formulated Preparations: Specific Monographs Tetracycline Capsules Tetracycline Capsules General Notices Action and use Tetracycline antibacterial. DEFINITION Tetracycline Capsules contain Tetracycline Hydrochloride. The capsules comply with the requirements stated under Capsules and with the following requirements. Content of tetracycline hydrochloride, C H N O ,HCl 22 24 2 8 95.0 to 105.0% of the stated amount. IDENTIFICATION A. Carry out the method for thin-layer chromatography , Appendix III A, using silica gel H as the coating substance. Adjust the pH of a 10% w/v solution of disodium edetate to 8.0 with 10M sodium hydroxide and spray the solution evenly onto the plate (about 10 ml for a plate 100 mm × 200 mm). Allow the plate to dry in a horizontal position at room temperature for at least 1 hour. Before use, dry the plate in an oven at 110° for 1 hour. Use a mixture of 6 volumes of water, 35 volumes of methanol and 59 volumes of dichloromethane as the mobile phase. Apply separately to the plate 1 µl of each of the following solutions. For solution (1) extract a quantity of the contents of the capsules containing 10 mg of Tetracycline Hydrochloride with 20 ml of methanol and centrifuge. Solution (2) contains 0.05% w/v of tetracycline hydrochloride BPCRS in methanol . Solution (3) contains 0.05% w/v of each of tetracycline hydrochloride BPCRS, chlortetracycline hydrochloride BPCRS and doxycycline hyclate BPCRS in methanol . Dry the plate in a current of air and examine under ultraviolet light (365 nm). The principal spot in the chromatogram obtained with solution (1) is similar in position, colour and size to the principal spot in the chromatog