Two types of pipettes (only two that I am aware of!) are used for measuring small volumes. A pipette is basically a turkey baster but much more accurate and precise. The first type has a dial that you use to tell the device how much it should suction. This type works mostly in microliters. Do you have any idea how small a microliter is? There are about 40-50 microliters to a drop of water (depending on pressure, temperature, etc.). So we pull up 10 (or some such number) microliters in this pipette and put it in a different container, like a tube. Every time that we are introducing a new reagent (ree-agent. Fancy word for ingredient), we need a new tip for the pipette. You draw up a bit in that tip, eject the tip in the disposal container, and grab a new tip. We go through at least 10 of these tips a day, and as much as 50.
The second type of pipette is for larger volumes. For amounts of liquid that are larger than 1 milliliter (ml), we use this second type. There is a handle that is sort of like a hand-gun. It has two triggers. One pulls liquid up, and the other pushes liquid down. This is done by way of a pump mechanism in the handle. This pipette also has tips. However, each tip is a long glass tube of at least 10 inches in length. These are marked along the side with ticks for varying amounts of volume. You could put in a 50 ml tip or a 10 ml tip or anything between. These are not nearly as accurate as the smaller volume pipettes because you are using your eyes rather than calibrated machinery. These are used when it is OK to be approximate. Whenever a "recipe" calls for 10 ml of this reagent, it means around 10 ml. These tips that are specially calibrated and marked (and have a filter at the top to make it harder to destroy the handle by pulling up too much liquid) get disposed of after each use as well. I imagine they are the more expensive type as they are glass.
We also use a type of non-calibrated, non-filtered glass tip. This is to get rid of waste liquid. You attach it to a vacuum tube and it sucks away liquid stuff. Each of these has to be disposed of after use or if you change the type of liquid you are vacuuming.
These latter types get used whenever you are doing tissue culture, as you are working with "large" amounts of liquid, and have plenty of waste.
There is also the issue of gloves. Every time you enter a lab it's a new pair of gloves. When you leave (even if you are coming back), you throw them away.
Then the cost of reagents. A lot of things are for general use and come in large quantities. Sometimes you get something that is at a high concentration and you only use it at low concentrations. It lasts a while. Sometimes however, you need something that is very particular or of particularly high quality. A little vial that has 1 ml (20 drops of water worth) in it can sometimes cost as much as $300 (probably even more than that). Even the more common, bulk ones are not so cheap. A half-liter of PBS (Phosphate Buffered Saline), a reagent that we use quite often, is more than $30. We generally use 10 ml per plate. If we are doing 20 plates, that is 2/5 of a bottle. Trypsin, which is used in pretty much everything, is $40-$100 for 100 micrograms, depending on the grade (the lower grade can be used for many things).
Gels, which are used to see whether the proteins or DNA you were looking for are actually present, run upwards of $40 each. Ones that are actually useful for what we do run upwards of $60 each.
I have not gone into any of the one time costs such as the initial investment in a piece of machinery. Nor have I gone into utility cost (I'll let you guess; hint- it's astronomical).
What I am trying to get at here is that science is expensive. I probably think about the cost too often. I am afraid of how much I cost, in that I am not experienced and therefore my work is not as efficient or correct as a more-well-trained individual. I will keep on trying and spending your tax-dollars though!
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