Endy:Preparing Antibiotic Stocks

Tetracycline

Stocks & Usage

• Stock Concentration - 5mg/ml in 70% Ethanol
• Aliquots - 200μl and 1ml
• Working Concentration - 20μg/ml

Preparation of 80ml stock solution

• Tetracycline is kept in the 4C fridge in 68-564D. It is light sensitive.
• Weigh 400mg of tetracyline HCL into a small weigh boat.
• Dilute 95% Ethanol to 70% using milliQ water.
  • Adding 20ml of milliQ to 60ml of 95% ethanol gives 80ml of 71% ethanol.
• Add 80ml of 70% Ethanol to a 250ml bottle.
• Add the tetracycline HCL to the ethanol.
• Mix/vortex vigorously so all the tetracycline goes into solution.
• Filter sterilize the solution into a falcon tube using a 20ml syringe and a 200nm filter.
• Aliquot into pcr tubes and 1.7ml eppendorfs.
• Store at -20C and protect any unused stock solution from light.
• Store the small aliquots in the small box and the big aliquots in the larger box.