For the past couple days I've been struggling with noob questions. This is to be expected, but not questioning your whole understanding of acid/base chemistry. I found several protocols for crystalizing my protein, all fortunately starting with just ordering it from the Internet, as my protein is readily available. (usually there is weeks to months of ramp up time depending on what you can borrow from other scientists.)
The next steps are to dissolve the lyopholized protein powder in distilled water, then adjust the pH to 5.5 using NaOH, also known as sodium hydroxide or lye. A strong base... pH 14 at 1M concentration, for those who forget how pH works. Now, normal water starts at pH 7, so how am I going to add 14 to 7 and get 5.5?
I thought I had the answer as I'm also supposed to mix in 50% methanol. pH is only well defined in water, so I spent hours looking up how organic solvents affected "apparent" pH and doing a deep literature search and generally questioning my sophomore chemisty.
Finally, team leader reads the methods, laughs at me, and points out that proteins are quite acidic and I had to compensate that. I had briefly considered this, but naively assumed that they wouldn't be THAT acidic. Shows what I know.
Er, trust me, I'm a professional.
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