- Perfect balance
- Band it like…
- Airing grievances
- A little bit of bubbly
- pHeeling lazy
While we’re on the topic of spinning things down in the centrifuge, I’ve found it rather cumbersome having to fill balance tubes before each spin. If you pre-fill tubes of varying volumes (e.g. 1 mL, 3 mL, 5mL and so on) and place them just next to the centrifuge, it’ll be awfully convenient to just reach over and find the perfect counterweight every time.
Do you ever get tired holding a reagent tube against the vortex shaker while waiting for its contents to mix or dissolve properly? If it takes longer than five minutes, you may want to strap your tube to the vortex shaker platform using a rubber band for hands-free agitation while you do something else.
If there aren’t any rubber bands lying around, take a pair of scissors, snip off the elastic bands at the wrists of some gloves and you’ll have your rubber bands to bind and tie whatever you wish.
So, you’ve noticed that the carbon dioxide tank for your cell culture incubator has been emptying really quickly over the past week. But where’s the leak? You could search for it by feeling around for unexpected air flows using your bare skin, but here’s a better way. Take some soap and rub it around the gas regulator and various other tubing connection points between the gas tank and the incubator. You’ll see bubbling wherever there’s air is escaping.
Bubbles may cause distress when they appear right in the middle of your gels and blots, but there are some situations where they can be useful as indicators of whether a solution contains proteins, serum or detergent. For example, if the label falls off your bottle of cell culture medium and you’re unsure whether fetal bovine serum has been added to it, give the bottle a hard shake. If bubbles form, your cell culture medium probably already contains serum.
If you’re paranoid and have the habit of always calibrating the pH meter before using it, you can stop doing that. Simply rinse off and immerse the pH probe in phosphate buffered saline. If the pH meter reads 7.4, there’s no need for calibration—you’re good to go!
