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Yep, Sandy's suggestion is

Sandy's suggestion is good. Practice with ANYTHING that has a cap. (That was my homework to a couple thousand HS freshmen!)

1. Completely loosen the cap being careful not to touch the bottom rim.
2. Using your index finger and thumb, take the cap off slightly so you are sure you can reset it and remove it easily.
3. ASEPTICALLY remove the cap by encircling it with your pinky. (Practice holding the cap in your pinky as you snap your fingers.

With this method, the opening of the cap stays down as you perform the rest of your task.
4. Right after you remove your sample, you can set the lid back over the vessel, but you can again pick up the cap with your pinky.

You can practice this on your kitchen bench or dining table.
Put out a drinking glass, a dessert plate and a small bowl (and fit the plate over the bowl), a knife or spoon or a straw and some ketchup or mayo or mustard, even if the bottle has a squirt cap. Loosen the squirt cap to expose the contents. (You can use the plate and bowl as if it were a Petri plate and lid.)

Keep in back anything you are NOT using at the moment.

Move forward anything you are transferring from or to.

In my lab, we stopped spraying caps with EtOH because there was one spark-induced fire in a TC hoods (that was used nearly constantly). You can keep a bottle of 70% right outside and use a dampened paper towel, but it's really not necessary unless your company's GMP requires this.

Loading serological pipettes into their pipettors:
Consider the double lines near the plug as the line you do not cross.
Hold the pipette between the double line and the plug so your hand is UNDER the pipette.
Plug into the pipettor so it feels relatively firm. The double line should still be easily visible.

All the aseptic handling should be performable with your elbows near your torso.

Before I start an aseptic procedure, I sit or stand where the work will be done and go thru in my mind how each step will go and look including where my hands will be, then reset whatever I notice could be placed better (and have been doing cell culture since 1967). Mindful aseptic handling.
Toby Horn


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