I am looking to measure low concentrations of dissolved formaldehyde in solution (down to potentially nanomolar levels). Does anyone know of a method of analysis capable of doing this accurately? I have a method for GC-MS analysis but cannot seem to detect much below 1 micromolar levels repeatably. I have tried to optimise the program to no avail so thought best to ask if there were any alternative methods available.
Here is a method that uses a microbalance.
http://phys.org/news/2011-08-net-nanodetector.html
Regards,
Joachim
Hi Joachim,
Formaldehyde is reactive and might be challenging to separate and detect without prior derivtization with (e.g., PFBHA). I have worked with SPME and headspace derivatization of formaldehyde. Method detection limits are in low ppb levels (or lower with some additional effort to optimize a method.
Jacek
There are a number of methods for water - most use HPLC with derivitization. I routinely analyze this compound in air using DNPH derivitization. It is a very stable method and extremely repeatable. The US EPA has a number of methods that you could reference and develop. Method 1667 is a drinking water method -> http://water.epa.gov/scitech/methods/cwa/bioindicators/upload/2007_07_10_methods_method_1667.pdf
One note of caution - there are many carbonyl compunds that are derivitized, and it would be advisable to order a multi component carbonyl standard to be sure that you are resolving and isolating formaldehyde. Typically the formaldehyde is well resolved, and will be the 1st peak after the DNPH front.
Another good reference would be method TO11A - This is the air method, it has better chromatography details - but same concept. see attachment for chromatography.
good luck!
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