CH332 Lab 8: HPLC WARS
Year three of this favorite student lab!!!! Two groups will make their own HPLC to separate a
mixture of R-hydroxybenzoic acids. You will give an oral presentation explaining your HPLC instrument
and its ability to separate the mixture and the evaluation of the retention time (peak analysis) that was
necessary to complete the separation.
This two week lab will test the analytical skills of two teams of CH332 students competing to
build the best HPLC instrument for the least cost. Each team will purchase HPLC components from our
stock of old HPLC parts (the store) and assemble the components into a working instrument capable of
separating methyl, ethyl, and propyl 4- hydroxybenzoate (parabens):
where R symbolizes an alkyl group such as methyl, ethyl, propyl or butyl.
PRE-LAB: Work with your team members to identify the parts you need to build an operational
HPLC. Each group will take turns purchasing components from the store. If you don't come prepared the
other team will be in a position to buy all the good stuff.
HAND IN: Well documented excel calculations for retention time, number of theoretical plates and the
cost per theoretical plate, and a copy of your chromatogram.
There is no written report. Instead, your group will give an oral presentation that includes:
1.
2.
3.
4.
Calculate the resolution of your instrument.
Calculate the number of theoretical plates.
Calculate the cost of your instrument and the ratio of plate number vs. cost.
Suggest improvements to your instrument.
Rules of the Competition
1.
2.
3.
4.
Purchase instrument components
1. We will flip a coin to determine who will buy the fist part. Each team will take turns
purchasing parts.
2. You do not need to purchase "extra" parts, but you may horde spare parts if you want.
3. You may purchase extra parts from the store or the other team at any time. Teams may
set their own price for parts and receive credit for sales to other teams. The store charges
a 50% restocking fee if you want to return parts to the store.
Each team is responsible for assembling their instrument. You may use the Logger Pro data
acquisition system available in the lab at no cost.
1. Ask questions if you don't know how parts fit together.
2. Most instruments have manuals available on the web.
3. You must get clearance from the lab instructor before turning on the HPLC pump.
Test you HPLC using a mixture of methyl, ethyl, and propyl 4-hydroxybenzoate. For full credit
you should be able to achieve baseline resolution of the three compounds.
Your group will give an oral presentation that includes:
1.
2.
3.
4.
Calculate the resolution of your instrument.
Calculate the number of theoretical plates.
Calculate the cost of your instrument and the ratio of plate number vs. cost.
Suggest improvements to your instrument.