The solution: extraction on metal vaporized analytical filters!
Metal vaporized filters offer a number of unique advantages that are not available with conventional filters. Scanning electron microscopy provides material contrast to all organic particles.
For light-optical microscopy and FTIR spectroscopy, optical methods can be used to obtain a better contrast to particles. In FTIR in particular, the surface of the metal filter enables reflection measurements which, in contrast to the ATR technique, can be automated, allowing organic particles to be measured cost-effectively.
Further information can be found here.