How to Handle Bacteria and Fungi on Receipt

Agar Slants
Some NCPF cultures are supplied as agar slants; these should be promptly sub-cultured on receipt.

Freeze-Dried Ampoules

Identify the culture by the number on the paper inside the ampoule, reading from the round end of the tube. The vacuum of each ampoule is checked before dispatch and should be confirmed if a high-frequency vacuum tester is available. Care should be taken in opening the ampoule as the contents are in a vacuum.

Make a file mark on the ampoule near the middle of the cotton wool plug and apply a red-hot glass rod to crack the glass.

Allow time for air, filtered by the plug, to seep into the ampoule and then gently remove the pointed top part. If the pointed part is snapped off suddenly the plug may be drawn to one end and hasty opening may release fine particles of dried organisms into the air of the laboratory. The plug may be impregnated with dried culture, and should be regarded as dangerous to handle and removed with forceps.

Flame the open end of the tube and insert a sterile cotton wool plug (e.g. the plug from a Pasteur pipette). The discarded plug and the pointed end of the ampoule should be treated as infected and autoclaved.

With a Pasteur pipette, add about 0.5 ml of broth, when necessary enriched with blood, to the ampoule and mix the contents carefully to avoid frothing or creating aerosols.

According to the gaseous and growth requirements, the broth suspension should be sub-cultured on to a suitable medium or media, preferably chosen to include a solid medium, both to obtain single colonies and to detect aerial contaminants which may be introduced during the opening of the ampoule. Ampoules of HAZARDOUS PATHOGENS (see Conditions of Supply of microbial pathogens: Safety) should be opened under appropriate Advisory Committee on Dangerous Pathogens containment level, and in an exhaust protective cabinet, designed to protect the worker against inhalation of aerosols (in the UK, a Class I or Class III cabinet).