Determination of BHA / BHT in essential oils

[WK]

I am currently performing this analysis by GC-MS since there are always many co-elutions.
Does anyone know of an simple HPLC method for this analysis?
I have tried a reverse-phase on BDS-C18 with 280nm but I still have co-elutions on my samples.
Perhaps you use SPE in sample preparation.
Thank you in advance for any replies.

[Consumer Products Guy]

I've assayed for BHA and BHT in various matrices and consumer products (surprise!) by HPLC, but low levels of analyte make it somewhat difficult to resolve these in certain matrices. I've used GC-FID (as well as GCMS) for these, works well. There's an early capillary GC paper on BHT assay in bar soaps that uses trimethylsilyl derivatization, and found that it works well. Capillary GC without derivatization can be OK but BHT can coelute with p-t-bamhca on DB-1 type columns; BHT-TMS can coelute with celestolide. See Goldstein, M. M., K. Molever, and W. P. Lok, "Quantitative Determination of BHT in Soap Products by Capillary Gas Chromatography," JAOCS, Vol. 59, No. 12 (December 1982), pp. 579-582.

[LY]

Hi!
I was developing HPLC methods for BHA determination in the pharmaceutical formulation and you welcome to try it:

Column: Symmetry, C18, 3.5 μm (4.6 mm x 75 mm), Waters;
Mobile Phase: Glacial acetic acid 0.4% solution: Acetonitrile (60:40 v/v)
Flow Rate; 1.5 mL;
Wavelength: 290 nm;
Injection V; 50 μL;
Temperature: 30oC + 2 oC
Run Time: 10 min
Diluent: 60% - Ethyl Alcohol Solution

2-BHA peak Retention Time (RT) about 5.5 min, 3-BHA peak RT about 6.5

GOOD LUCK!