Methylene Blue Injection, Veterinary
Methylene Blue Injection, Veterinary is a sterile solution of Methylene Blue in Water for Injection. It contains NLT 9.5 mg/mL and NMT 10.5 mg/mL of methylene blue trihydrate (C16H18ClN3S·3H2O). Prepare Methylene Blue Injection, Veterinary as follows (see Pharmaceutical CompoundingSterile Preparations 797):
Dissolve an accurately weighed quantity of Methylene Blue in Sterile Water for Injection or Sodium Chloride Injection (0.9%), and dilute to volume, with mixing. Sterilize by a suitable means, such as sterile filtration or autoclaving.
• A. The visible absorption spectrum of the Sample solution exhibits maxima and minima at the same wavelengths as that of the Standard solution, concomitantly measured as directed in the Assay.
• B. Thin-Layer Chromatographic Identification Test 201
Diluent: Methanol and water (1:1)
Standard solution: 5 mg/mL of USP Methylene Blue RS in Diluent
Sample solution: Dilute a portion of the Injection with an equal volume of methanol.
Application volume: 1 µL
Developing solvent system: Alcohol, acetic acid, and water (3:3:4)
Samples: Standard solution and Sample solution
Allow the spots to dry, and develop until the solvent front has moved about 10 cm above the line of application. Remove the plate from the chamber, and allow the solvent to evaporate.
Acceptance criteria: The RF value of the principal spot from the Sample solution corresponds to that from the Standard solution.
Standard solution: 2 µg/mL of USP Methylene Blue RS in diluted alcohol
Sample solution: Dilute a volume of Injection with diluted alcohol to obtain a solution with a nominal concentration of about 2.4 µg of methylene blue trihydrate (2 µg of anhydrous methylene blue)/mL.
Detector: 663 nm
Cell: 1 cm
Samples: Standard solution and Sample solution. Concomitantly determine the absorbance of both solutions, using diluted alcohol as the blank.
Calculate the quantity, in mg, of C16H18ClN3S·3H2O in each mL of Injection taken:
Result = (AU/AS) × (CS/CU) × L × (Mr1/Mr2)
Acceptance criteria: 9.510.5 mg/mL of C16H18ClN3S·3H2O
• pH 791: 3.04.5
• Bacterial Endotoxins Test 85: NMT 0.17 USP Endotoxin Unit/mg of methylene blue
• Sterility Tests 71: Meets the requirements
• Other Requirements: It meets the requirements under Injections 1.
• Packaging and Storage: Preserve in single-dose containers, preferably of Type I amber glass. Store at room temperature, protected from light.
• Labeling: Label it to indicate that it is to be discarded after its beyond use date, to state that it is to be kept out of the reach of children, and to indicate the nominal content of methylene blue in the Injection and whether it was prepared in Sterile Water for Injection or in Sodium Chloride Injection (0.9%). Label it to indicate that the dose is not to exceed 30 mg of methylene blue/kg of body weight/h. Label it to indicate that it is for veterinary use only and to state the Beyond-Use Date.
• Beyond-Use Date: NMT 365 days after the date on which it was compounded
• USP Reference Standards 11
USP Endotoxin RS
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USP35NF30 Page 3876Pharmacopeial Forum: Volume No. 34(6) Page 1461