I suspened my biological samples in phosphate buffer.
Not sure I understand your question correctly. If the question is: can you perform an aqueous extraction using phosphate buffer, the short answer is "yes, but..."
"Yes" you can use PBS for aqueous extraction and anything that goes in this phase qualify as an aqueous extract.
"But..."phosphate buffer has 1) high salinity compared to pure water, low compared to brine. That can change the extraction of some hydrophobic organics 2) the pH being buffered, it can can change the extraction of acids and bases depending on their pKa. For instance, it can force the deprotonation of amines, reducing their solubility in the aqueous phase.
To conclude, if your use of PBS was intentional then there is no problem: what you have in it qualify as an aqueous extract. If this was accidental and you usually use brine or pure water in your protocol, I would suggest to do it again because the buffered pH and salinity modify the extraction process.
- Badges
- Science method