Hello,

I think you have to use a clean-up method after extraction. The choise of clean-up procedure depends mostly on the physico-chemical properties of your pesticides. You can also use an extraction method that not solves the hole leave and the included compounds like chlorophyll but that is softer and extrats mostly your pesticides (depends on your question: if you want to determine total pesticides within the plant than you have to solve the hole leave, but if you want to determine pesticides on the leave than you can use a soft extraction solvent and only solve the surface of the leave, resulting in less co-extracted compounds). A good overview of extraction methods and  clean-up procedures (within the references) is given in Camel (2000): Microwave-assisted solvent extraction of environmental samples. Many studies are using solid phase extraction (SPE) for clean up, especially Florisil is known to be suitable for plant samples. But in more recent studies also saponification is used to remove chlorophyll of the extract. I hope you ll find a suitable method,

best wishes,

Melanie Bläsing

You may try using activated carbon. Chlorophyll has strong affinity for it.

Use graphitized carbon black to absorb chlorophyll. UCT developed new packing as well and it is called chlorofiltr and it should be even better with acetonitrile extract.

https://www.unitedchem.com/catalog/sample-prep/quechers/quechers-chlorofiltr

you can do clean-up for your extract by three layers, one represent the silica gel ; the second one composed of both silicagel ,and charcoal(the longest one), and the third one is anhydrous sodium sulfate as i did in my project for multi-residue analysis