[hopenaroz]

Hi everyone! I'm having some difficulties with preparing my solutions properly for dilution tests. I'm doing the A280 protein experiment and basically have to measure 7 dilutions of BSA solution on various instruments to obtain the absorbance value at 280nm. The molecular weight of BSA is 66463g/mol and the 7 dilutions I need are 10uM (micro molar), 5uM, 1uM, 0.5uM, 0.1uM, 0.05uM, and 0.01uM. I;m having trouble figuring out how much BSA I need to prep with water for my first solution of 10uM and then how to dilute it down to 5uM and so forth. Thanks in advance for the *delete me*

[billnotgatez]

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[Babcock_Hall]

What Bill said.  Also if memory serves me correctly, the molar absorptivity is a little less than 45,000.  Do you think that it is possible to observe the UV spectrum of bovine serum albumin at 0.01 µM in concentration?

[Arkcon]

Hi everyone! I'm having some difficulties with preparing my solutions properly for dilution tests.

No problem, we're glad to help a student.

I'm doing the A280 protein experiment and basically have to measure 7 dilutions of BSA solution on various instruments to obtain the absorbance value at 280nm.

This is a good summary, its not excessively detailed, given the rest of your question.  Which is nice.

The molecular weight of BSA is 66463g/mol

Not sure we really need this factoid, but at least its here if we do later.

and the 7 dilutions I need are 10uM (micro molar), 5uM, 1uM, 0.5uM, 0.1uM, 0.05uM, and 0.01uM.

OK.  Here's something you have to do: can you relate these to each other in some way?  The numbers themselves follow a suspicious pattern that we can use to solve this problem.

I;m having trouble figuring out how much BSA I need to prep with water for my first solution of 10uM

OK.  This needs some work, that you have to start with.  You have the molecular weight, how will you relate that to grams, moles, molar solutions, and then micromolar (uM)?

and then how to dilute it down to 5uM and so forth. Thanks in advance for the *delete me*

Hrm.  Do you still need help here?  I give you ten pennies, I stack them in a pile, I tell you I want 5 cents.  Can't you give me half the pile?   Try to solve this problem along those lines for yourself.