Is inductor saturation current frequency dependent?
The saturation itself is AFAIK not frequency dependent (though I am not 100% sure, ferrites have all kind of weird properties when the operation frequency increases). What you definitely get is that the permeability decreases and the loses increase. Which means, your inductor will behave slightly different if you go up in frequency. Depending on the exact core material used, this change can be quite abrupt and can cover several orders of magnitudes.This will make your inductor behave like a non-linear element if you get close to that frequency. If you know what kind of core material has been used, you can check the manufacturers datasheet. To get an idea how ferrites behave, you can have a look at the catalogs of Fair-Rite or TDK, which contain quite a bit of data.