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Category Corticosteroid (ophthalmic); anti-inflammatory (steroidal); antibacterial.

      Hydrocortisone Acetate and Neomycin Sulfate Eye Ointment contains not less than 90.0 per cent and not more than 110.0 per cent of the labelled amount of C₂₃H₃₂O₆, and the equivalent of not less than 90.0 per cent and not more than 135.0 per cent of the labelled amount of neomycin.

Strength available 1.5 per cent w/w of Hydrocortisone Acetate and 0.5 per cent w/w of Neomycin Sulfate (equivalent to 0.35 per cent w/w of neomycin base).

Dose Topical, to the conjunctiva, three or four times a day initially, with frequency of application gradually being decreased as inflammation subsides.

Contra-indication; Warning; Precaution; Additional information See under Hydrocortisone Acetate, p. 117 and Neomycin Sulfate, p. 132.

Labelling The label on the container states the quantity equivalent to the amount of neomycin.

Identification

      A. Carry out the test as described in the “Thin-layer Chromatography” (Appendix 3.1), using silica gel G as the coating substance and a mixture of 4 volumes of methanol, 2 volumes of 2-propanol, 2 volumes of dichloromethane, 2 volumes of strong ammonia solution, and 1.5 volumes of water as the mobile phase. Apply separately to the plate, 10 μl of each of the following solutions. For solution (A) transfer a portion of the ointment containing 3.5 mg of neomycin to a 15-ml centrifuge tube. Add 4 ml of chloroform to the centrifuge tube, and shake well to disperse the ointment. Add 1 ml of 0.1 M hydrochloric acid, vortex for 4 minutes, centrifuge and use the clear supernatant. For solution (B) dissolve a portion of Neomycin Sulfate RS in 0.1 M hydrochloric acid to obtain a solution containing the equivalent of 3.5 mg of neomycin per ml. After removal of the plate, dry at 105º for 10 minutes, spray with a 0.2 per cent w/v solution of ninhydrin in 1-butanol, and heat at 105º for 5 minutes: the principal spot in the chromatogram obtained from solution (A) corresponds to that obtained from solution (B).

      B. The retention time of the major peak for hydrocortisone acetate in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay for hydrocortisone acetate. 

Water Not more than 1.0 per cent w/w, 20 ml of a mixture of 7 volumes of toluene and 3 volumes of methanol being used in place of methanol in the titration vessel (Karl Fischer Method, Appendix 4.12).

Assay

      FOR HYDROCORTISONE ACETATE Carry out the determination as described in the “High-pressure Liquid Chromatography” (Appendix 3.5).

      Mobile phase Prepare a mixture of 475 volumes of butyl chloride, 475 volumes of water-saturated butyl chloride, 70 volumes of tetrahydrofuran, 35 volumes of methanol and 30 volumes of glacial acetic acid. Make adjustments if necessary.

      Standard preparation Dissolve an accurately weighed quantity of Hydrocortisone Acetate RS in water-saturated chloroform to obtain a solution having a known concentration of about 100 μg per ml.

      Assay preparation Transfer an accurately weighed quantity of Hydrocortisone Acetate and Neomycin Sulfate Eye Ointment, containing about 2.5 mg of hydrocortisone acetate, to a stoppered centrifuge tube. Add 25.0 ml of water-saturated chloroform and 10 glass beads. Securely close the container, and shake vigorously for approximately 15 minutes. Centrifuge, and use the clear, lower chloroform layer.

      Chromatographic system The chromatographic procedure may be carried out using (a) a stainless steel column (30 cm × 4 mm) packed with porous silica particles (10 μm), (b) Mobile phase at a flow rate of about 1 ml per minute and (c) an ultraviolet photometer set at 254 nm.

      To determine the suitability of the chromatographic system, chromatograph Standard preparation, and record the peak responses as directed under Procedure: the relative standard deviation for replicate injections is not more than 2.0 per cent.

      Procedure Separately inject equal volumes (about 10 μl) of Standard preparation and Assay preparation into the chromatograph, record the chromatograms and measure the responses for the major peaks.

      Calculation Calculate the content of C₂₃H₃₂O₆ in the portion of the Ointment taken, using the declared content of C₂₃H₃₂O₆ in Hydrocortisone Acetate RS.

      FOR NEOMYCIN SULFATE Transfer an accurately weighed portion of Hydrocortisone Acetate and Neomycin Sulfate Eye Ointment, containing about 3.5 mg of neomycin, to a separator, add 50 ml of ether, shake and extract with four 20-ml portions of Buffer 2. Combine the aqueous extracts, and dilute with Buffer 2 to an appropriate volume to obtain a stock solution of convenient concentration. Dilute this stock solution quantitatively and stepwise with Buffer 2 to obtain a solution having a concentration assumed to the median dose level of the standard and proceed as directed under the microbiological assay of Neomycin Sulfate according to the “Microbiological Assay of Antibiotics”(Appendix 6.10).

Other requirements Comply with the requirements described under “Eye Preparations” (Appendix 1.16).