[MS.phy]

Please suggest some methods for determining the ibuprofen content in tablets, capsules and liquid dosage forms.

Is there a method which this can be done using UV spectroscopy?

[Arkcon]

The relevant pharmacopeia will have the method for you.  If subscribing to the pharmacopeia is outside of you're scope, you should tell us what your scope is, as specifically as possible.  A quick Google didn't point me to a UV method for ibuprofen.  I don't believe there's one even for acetaminophen, although I do know that many pharmacopeia methods do use a UV method for aspirin.

[MS.phy]

Thanks Arkcon

I have done an exhaustive search of the pharmacopeia and have tried several methods from it, but due to equipment limitations I need some other methods not included in the pharmacopeia..

A UV method for an Ibuprofen complex would also be suitable for me.

[Arkcon]

Thanks Arkcon

We're always glad to help.

I have done an exhaustive search of the pharmacopeia and have tried several methods from it, but due to equipment limitations I need some other methods not included in the pharmacopeia..

You have not yet told us your scope.  You have a pharmacopeia, relevant for the jurisdiction for which the product will be sold.  I guess.  You haven't said that's true.  Whatever national group that applies.  Which you also haven't said.  I'm a MOD: so I can see your IP address, and guess your nation, do I have to?

My quick search of the US pharmacopeia tells me the assay for raw material purity is HPLC.  You tried this, you said?  But you have instrument limitations, so you didn't I guess?  Also, you will need different method for different dosage forms. 

Where are you in addressing your challenge.  How far have you gone?  How far do you need to go?

Are you in high school?  Are you in an advanced high school course?  Are you learning the concepts in a university?  Are you a produced of small OEM batches of pharmaceuticals?

A UV method for an Ibuprofen complex would also be suitable for me.

You can try to develop one.  Do you know of the limitations and problems you might face?  A validated analytical method, developed for you by a testing laboratory, would cost you upwards of $100,000 USD.  I unfortunately don't have analytical instrumentation at my home, or I would gladly develop one to your standards for $99,999 USD, plus $1 handling fee.

[MS.phy]

A bit of context. I have an undergraduate project assignment to determine Ibuprofen for various dosage forms. I need several methods to satisfy the project requirement. I have done a HPLC method as per pharmacopeia but now I need more methods.

[Arkcon]

A bit of context. I have an undergraduate project assignment to determine Ibuprofen for various dosage forms.

Excellent.  Now.  At what wavelengths, that a spectrometer will work at, does ibuprofen absorb? At what wavelengths do the excipients absorb?  Can you find those out, by searching the internet, or can you determine them experimentally, using your instrument.

I need several methods to satisfy the project requirement.

Interesting.  Have you considered other methods?  Wet-chemistry reactions?  Gravimetric?  Hey listen, you just said this is an undergraduate course, we've gone away from industry, so you can now try anything.

I have done a HPLC method as per pharmacopeia but now I need more methods.

Great.  You now have a "gold standard" method to compare the results of your new tests to.

[MS.phy]

Unfortunately it seems the HPLC machine had a damaged column when I used it so my HPLC results are not good but that's life.

Some of the possible such as IR have been deemed not accurate for this so options seem very limited now.

With the equipment at hand it looks like the best approach is to do the UV spectroscopy with a ibuprofen-copper complex. Preparation and analysis of this complex is going to be difficult within my 4 hour time limit.