General Lab Maintenance

Washing Dishes

• Always wear gloves
• Scrub dishes thoroughly with a brush, Alconox, and hot water. Make sure that all precipitate or stains are removed from the glassware.  Stubborn stains can be soaked overnight or put in the microwave for a few seconds.
• Rinse 5 times with tap water. Rinse 2 times with deionized water.
• It is very important that all traces of soap be removed from glassware. Therefore, do not skimp on the rinsing steps!
• Let dishes air dry on drying rack.
• Test tubes can be dried upside down in a test tube rack. The Morten closures (plastic or metal caps) can be air-dried in a wire basket with a paper towel underneath it.
• When the dishes are clean and dry, they can be put into cabinets. Cabinets are labeled with the type of glassware that should be stored in them.

Acid Bathing

• When glassware was used with metals that are hard to remove, they can be soaked in an acid bath
• Be sure not to leave glassware in the acid bath for longer than 24 hours, as this can damage the glassware
• Rinse the glassware as best you can
• Wearing acid gloves, slowly submerge your glassware such that none of the liquid in the bath splashes up or bubbles excessively
• Allow your glassware to soak no longer than 24 hours
• Wearing acid gloves, slowly remove your glassware from the acid bath
• Rinse 5 times with tap water and 2 times with deionized water
• Let glassware air dry on drying rack

Washing Glass Pipets

• Put the pipet washer in the sink and attach the hose to the inlet.
• Place an Alconox tablet into the water and turn the water on at a low flowrate.
• Make sure that the pipets are placed into the basket with the tip (narrow end) end up. Add the pipets to the washer.
• Allow the washer to cycle 12-15 times, or until the pipets are thoroughly free of detergent.
• Cleaned pipets can be placed into a clean receptacle until they can be dried and autoclaved.

Aseptic Technique

• Dark-striped autoclave tape on a container indicates that whatever is inside is sterile and should remain as such
• When extracting something from a sterile container, minimize the amount of time that its lid is off, use only sterile instruments to extract liquids, and shake out solids

Biosafety Hood

• Turn on the vent on the hood and allow it to run for at least 10 minutes before use
• Spray your gloved hands with alcohol and rub it in
• Spray and wipe the inside surface of the hood with alcohol

Packing Pipet Tips

• Wear gloves.
• Pack tips into the boxes.
• Put autoclave tape on each box.
• Put into autoclavable container and autoclave on a gravity cycle (20 minutes steam + 10 minutes drying time).
• Place autoclaved boxes on the shelf when dry.

Making LB Medium in Test Tubes

• Add 20 g of LB to 1 liter of distilled deionized water. Do this in a 1-liter bottle.
• Swirl to completely dissolve the LB.
• Screw the dispensing unit to the top of the bottle. Set the dispenser to 5 mL.
• Dispense 5 mL to clean, dry test tubes that are in an autoclavable rack.
• Cover each tube with a Morten closure.
• Put one piece of autoclave tape on each rack. Place rack in autoclavable container.
• Autoclave on liquid cycle (20 minutes steam + 0 minutes drying time).
• Place on shelf when cool.
• Prepare new tubes when there are less than 20 tubes left

Making LB plates

• Add 20 g of LB and 16 g of agar to 1 liter of distilled deionized water. If you want, a stir bar may be added to the flask.
• Do this in a 2-liter Erlenmeyer flask or split the 1-liter volume into two 1-liter flasks. (You do not want to put 1 liter of fluid into a 1 liter container in the autoclave because it will boil over.  It is best to only fill containers half full when they are going to the autoclave.)
• Turn on the water bath to obtain a temperature of about 65 ^o Do this before you put the medium into the autoclave.
• Autoclave on liquid cycle (20 minutes steam + 0 minutes drying time).
• Place the autoclaved flask(s) into the water bath to cool. You do not want to cool them at room temperature because the agar will solidify.  Therefore, they are cooled in the water bath.
• After 15 - 20 minutes, the plates can be poured.
• Do not shake the LB extensively because this will cause a lot of bubble formation. Bubbles are not desirable when you pour plates.  You can invert the bottle gently to mix, or stir it on a stir plate if you added a stir bar prior to autoclaving.
• Label the plates so that you know that they contain LB. You can use the lab color-coding scheme, or you can simply write “LB” on the bottom of each plate. 
• Lift up the lid; pour LB into each plate so that the bottom is completely covered; replace the lid. This should be done quickly so that the plates remain sterile.
• If some bubbles are entrapped in a plate, the plate can be briefly flamed with a Bunsen burner.
• One liter of medium will make about 2 sleeves of plates.
• Let the plates dry overnight in a stack (5-10 plates/stack) before storing them upside down in a plastic bag. If there is a lot of condensation on the lid, it can be shaken off before plate storage.

Making Plates 1.MP4

Filling Bottles

• Bottles containing ethanol, water, and soap are kept at the sinks. These should be filled with the appropriate fluid.
• Water bottles should be filled with distilled deionized water.
• Soap bottles can be filled with a sprinkling of Alconox and distilled deionized water.

General Lab Cleaning

• The sinks should be kept clean and free of clutter.
• The benches should be kept clean, and waste should be rapidly processed.
• The scale should be cleaned frequently.
• Use soap and hot water to wash the benches. Rinse several times with water.  Do a final drying step with ethanol.  (If you only use water to wash the benches, they will be sticky.)

Autoclaving

• Make sure that everything is placed into an autoclavable tray.
• If bottles are being autoclaved, make sure that the caps are loose. Otherwise, the bottles may explode.
• Make sure that the autoclave door is securely tightened.
• Remove materials promptly from the autoclave, in case others are waiting to use it.

Agar Post-Autoclave.MP4

Autoclave 2.MP4

Autoclaving biological waste

• Biological waste must be autoclaved prior to disposal so that we are not flushing viable organisms into the sewer.
• Place waste (liquids or biohazard bags) in an autoclavable tray. Autoclave on liquid cycle (30 minutes steam + 0 minutes drying time).   
• Autoclaved liquid waste can be put down the sink with the water running. The glassware can then be washed as usual.

Autoclaving Biological Waste Bags

• Don't wait until the bags are completely full because they will be too big to fit into the autoclave tray. Take care of the bags when they are 1/2 to 2/3 full.
• Put the biological waste bag into a second biological waste bag. This will prevent costly leaks in the autoclave.
• Put the waste into the large autoclavable tray. If the bag is too full to fit into the tray, separate the waste into 2 bags.
• Autoclave on liquid cycle (30 minutes steam + 0 minutes drying time).
• Put the autoclaved waste into a black garbage bag and tie securely. Place into the regular garbage for disposal.  The maintenance staff will not pick this up unless it is in an opaque garbage bag.

Weighing Balance

• While the balance is off, use a brush to gently clean around the balance
• Place the empty vessel in which you plan to weigh your sample (boat, paper, etc) on the balance
• If the reading on the balance is moving around, make sure the doors are closed and nothing is disturbing the inside
• Once the reading has stabilized, tare or zero the balance and place your sample into the weighing vessel
• Wait for the reading to stabilize again and record the reading
• Use a brush to clean the inside and outside of the balance once you are finished